Given that indoor tanning beds were officially classified as a human carcinogen in 2009 -- up there with cigarettes and asbestos -- it should be fairly obvious that frequent tanning-booth exposure would increase your risk of skin cancer.
Indeed, the evidence linking indoor tanning with melanoma, the deadliest form of skin cancer, and squamous cell carcinoma, one of the more common forms of the disease, is "convincing," according to the World Health Organization's International Agency for Research on Cancer. But the research concerning tanning beds and basal cell carcinoma, the third and most frequent major type of skin cancer -- which accounts for some 80% of all skin cancer cases in the U.S. -- has thus far been inconsistent. (See pictures of a photographer's intimate account of her mother's cancer ordeal.)
Basal cell carcinoma, a slow-growing cancer, has traditionally been a disease of middle age. But it's been appearing with increasing frequency in people under 40, especially in women -- a demographic that also happens to like indoor tanning -- suggesting a link. So researchers at the Yale School of Public Health sought to study the association.
The study included 376 people under 40, who had been diagnosed with basal cell carcinoma between 2006 and 2010. They were matched with a control group of 390 dermatology patients who were diagnosed with minor skin conditions like cysts and warts. All participants had skin biopsies, and all were drawn from a Yale University database.
The researchers interviewed each participant about their UV exposure -- both in tanning beds and outdoors. They also asked about their history of sunburns, sunscreen use, family history of melanoma and non-melanoma skin cancers, and their self-reported eye, skin and hair color.
The conclusion: people who had ever used a tanning booth were 69% more likely to develop early-onset basal cell carcinoma than never tanners. Those who used tanning booths more regularly -- for at least six years -- were more than twice a likely to develop basal cell carcinoma, compared with never tanners.
The study found that women were far more devoted than men to indoor tanning, which might help explain why 70% of all early onset basal cell carcinomas occur in females. The authors concluded that about 27% of cases of early onset disease -- including 43% of cases in women -- could be prevented if people simply stopped using tanning booths.
That's a tall order, considering that some 30 million Americans use indoor tanning beds each year. Policy changes, such as the recent California ban on teen tanning, may help, the authors suggest. So would behavioral interventions aimed at women -- at least one study in 2010 found that the best way to get young women to tan less was to warn them about the skin-wrinkling effects of tanning-bed exposure, not the risk of skin cancer.
"Importantly, indoor tanning is a behavior that individuals can change. In conjunction with the findings on melanoma, our results for [basal cell carcinoma] indicate that reducing indoor tanning could translate to a meaningful reduction in the incidence of these two types of skin cancer," said Leah M. Ferrucci, first author of the paper and a postdoctoral fellow at the Yale School of Public Health, in a statement.
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We all discover new web apps each year but not every one of them gets the recognition it deserves. With 2011 drawing to a close, we wanted to highlight the 10 we felt deserved a bit more hype. 
To start off the list, we're not singling out any one app in particular. We're focusing on the many little web apps that provide one simple feature or do one thing well. These are apps like Every Time Zone (an app that displays what time it is in every time zone), Umbrealla Today? (an app that gives you a weather report that is as simple as letting you know if you'll need an umbrella), and notepad.cc (which is just an instant notepad in your browser for whenever you need it). Additionally there's Spreeder, which helps you speed read any text and improve your reading comprehension, and SleepyTime, which calculates when you need to go to bed for the optimal wakeup time, and SimplyNoise, which is a simple white noise generator. There are too many to list here, but they're all pretty clever and useful. We could do an entire top 10 on these little guys, but that'll have to wait. For now, enjoy the previously mentioned six as well as 0to255, Mixest, PDFMyURL, and Copy Paste Character as well. (There, now you have 10!)
Aherk is an interesting web app that was designed to help you blackmail yourself. Let's say, for example, you have an embarrassing nude photo of yourself and you need to wash the dishes. Aherk! lets both of those things work in your favor. You provide Aherk! with the embarrassing nude, set a deadline, and then hopefully wash those dishes. If you succeed in washing the dishes, you post evidence on Facebook and your friends can vote if you completed the task sufficiently. If you did, you'll escape embarrassment. If not, Aherk! will release the photo. Assuming you have good, trustworthy friends and are motivated by fear, this is a neat and scary way to get things done.
Previously mentioned Asana is a free web app to help groups collaborate on multiple projects. The individual user will be able to keep track of his or her own responsibilities, dependent tasks, and sub-projects, and all of that individual activity will contribute to the whole. Users will be able to see what their coworkers are up to on a given project and quickly get updates without the need to check in. If you've got a team (or are on one) with a variety of projects that need management, Asana is a web app worth checking out.
Previously mentioned Cryptocat makes private instant messaging very simple. You just head over to Cryptocat, start a chatroom with a name of your choice, and send people the URL. Your chats will be encrypted and wiped out after the chatroom has had a one-hour period of inactivity. While spies and secret agents probably ought to use something a little more secure, it's a great private chat option for the rest of us.
Previously mentioned Teambox is a web app designed to help multiple people, on any kind of team, communicate better. Rather than assuming one method of communication is ideal, it takes a note from social media and other web paradigms to offer methods that best suit the type of communication needed. Status updates are handled like Twitter messages, complete with @ message functionality. Longer-form messages can be sent to teammates when necessary. Users can collaborate on lists and create pages, too, to help everyone collaborate using the best method possible.
It's hard to remember all the great and important stuff you come across each day, and so it helps to write it down or just dump the information anywhere else so you don't overload your brain. But physical and digital notes get lost or forgotten all the same, which is where Thinkery comes in. It's an app where you can just input anything you need to remember. There are a lot of apps that attempt to manage all kinds of information you might have on your brain, such as the popular Evernote, but Thinkery takes it a step further by interpreting what you tell it. For example, if you put in an Amazon link it'll know you're interested in a specific product and include the product information. If you prepend a word in a sentence with a # sign it'll automatically tag those words so you don't have to bother doing it manually. These are just a few examples, but there are more applications. Thinkery was designed to help you get your thoughts out quickly while still keeping them organized, and it does that very well.
Cloudtact is a web app that keeps your contacts in sync across all your devices and lets your contacts keep everything up to date so you don't have to make constant changes every time someone moves or gets a new phone number. You sign up, enter your own information, and then ask all your friends to submit their contact info. When they do, you can then sync all that information with Google, Android, your iDevice, and/or your Mac. If everyone you ask submits their contact info, you won't have to do much of anything?Cloudtact will keep everything up-to-date across your devices without any intervention on your part.
Pixlr is like having a simplified version of Photoshop in your browser. It's incredibly responsive, responds to practically the exact same keyboard shortcuts as Photoshop, and is very easy to use. You can import photos from various sources or start with a blank canvas. It even comes with complex layer support that allow for several blending modes and layer styles. If you don't have Photoshop handy and need to do some image editing in your browser, Pixlr is a really fantastic alternative.
Although we've discussed WorkFlowy in the past, and it has been around prior to 2011, we've been accused (by a few readers) of not giving WorkFlowy its due. Seeing as it's a really phenomenal, surprisingly rich list-making app. It feels a lot like a plain text document, but as you start creating your lists you realize you can navigate through each item like you're navigating a web site. You'll be able to input a ton of
If This Then That (or ifttt for short) is, by far, one of the coolest web apps we've come across this year?so much so we put together a complete guide with plenty of helpful examples. The basic premise is that ifttt performs an action if a certain condition is met. For example, if it checks the weather and it appears to be raining, you can set it up to send you a text message. If you get a new email from your mother, ifttt can initiate a phone call. Those are just a couple of examples. There's much more you can do. It's really one of the best tools to come along in quite awhile, so take the time to get to know it. Ifttt can seem a little intimidating at first, but you'll get the hang of it quickly. If you need help, or a few ideas to start with, be sure to check out our guide.
Not all gifts are conveniently rectangular. Sometimes the presents you buy your friends and family come in an odd shape, making them harder to wrap. Fortunately this is a problem people have been dealing with for a long time and have come up with a variety of good solutions. We picked four of the best to help you wrap your oddly shaped gift this holiday. 
Keltie Colleen from Mahalo.com suggests a simple yet attractive wrapping method. You just place the gift on a large sheet of wrapping paper, pull the edges around it up to the top like you're creating a sack, and then tie it up with some decorative ribbon.
YouTube user ThePort989 opts for standard wrapping methods, but cuts the wrapping paper to form-fit the present as she goes along. This will result in a more standard-looking wrapped gift but is a bit more effort than the previous method.
Although this video demonstrates the lotus wrapping method on a book, which has a very simple and regular shape, the same method can be used on oddly shaped presents. The wrapping method is very simply, in which you tie two of the wrapping material's corners together, reversing the ends to make it look like a lotus petals. Then you just repeat the same thing with the other two corners and it looks like a lotus flower on top. This works especially well if your wrapping material is softer and is different on each side.
Nilda Garcia from Kate's Paperie demonstrates how to wrap a tennis racket, which has an inconsistent shape. She folds tissue paper at odd angles to better fit the form. She also opts to use two sheets to wrap the bottom and then another two sheets to wrap the top so that the packaging she creates is sufficiently reinforced.