I came across this tutorial last week that showed how you can turn an ordinary phone camera into something capable of capturing extreme close-up macro photos. You know, the ones where you can see the hairs on a fly's head.
After the dust settled on the iOS 6 release, over the weekend I dug through the junk drawer in my kitchen and found an old laser pointer. I then located a bobby pin in the bathroom and some painter's tape in the basement. I now had the three necessary ingredients and the time to see if this thing actually works. Also, let me state I used an iPhone 4S, which features an 8-megapixel camera. Your mileage may vary, given the number of pixels your phone's camera packs.

OK, let's get started. First, unscrew or pop off the top of your laser pointer to get to the lens. In my case, after popping the top off, I unscrewed the top from the interior housing and out popped the lens. Next, wedge the lens into one of the grooves of the bobby pin.
Then all you need to do is line up the lens with the lens on your phone and tape it in place. Both sides of my laser pointer felt concave, so I wasn't sure which side should be facing out. (The tutorial I read said the convex side should face out while the flat side should face your phone, neither of which I encountered.) I found that one way resulted in a bit of a fish-eye effect, so I turned it around.
Once you have your DIY lens assembled, hold your phone close to, say, grains of salt or Honest Abe and snap a shot:
You have to get very close (but not too close) and hold your hand impossibly still in order to get a shot that's in focus. For mobile phone photographers, it's a fun, cheap, and easy way to obtain macro capability. Don't have an old laser pointer lying around? Then check out Sharon Vaknin's video about two other DIY macro lens methods (see below).
(via Apartment Therapy)