Night Vision Goggles
Since phone cameras pick up the IR spectrum, I though maybe I could create a night vision camera using one of my old phones and some IR LEDs. I also have a google cardboard like device that allows you to turn your phone into a virtual reality headset, which I thought would be perfect to make a set of night vision goggles. It actually worked out pretty well! After removing the IR filter from the phones camera, the "goggles" let you see pretty far in complete darkness.
I was hoping that the IR filter in the phone camera wouldn't interfere too much, but unfortunately that didn't turn out to be the case. I had to remove the IR filter from one of my old phones instead. I found a great tutorial on how to do that here: Modify Google Galaxy Nexus for NIR. It wasn't too difficult, but was a lot more involved than I was expecting. Here are some pics of the process
Once the IR filter was out of the phone camera, I started attaching some IR LEDs to the outside of the google cardboard. I bought some 'super bright' IR LEDs from amazon that can handle up to 100mA of continuous current each @1.6V forward voltage drop. I was going to put 9 of them on the front, but that seemed like total overkill after seeing how bright these things are, so I only ended up putting 6 on the front. I'm using a lithium ion battery pack from sparkfun to power the LEDs, and have a power switch attached to the cardboard that will turn them on and off.
See the video above and some of the images below for the finished product!