Adafruit, which posts the geekiest, most wonderful projects I'll never understand, tells you how to make your own "chameleon scarf," an accessory that changes color to match your clothing. The scarf itself is incidental, because what blew my mind is a sensor that detects the color of an object -a piece of fruit or the shirt you're wearing- and matches its RGB code. Then there are LEDs that change color depending on the code sent to them. The possibilities are endless, if you know a little about electronics. Find a video that shows how it works, and links to pages of information behind this project at Adafruit. Link -Thanks, Becky Stern!
(Image credit: Johngineer!)
Just stare at her face for like 30 seconds and tell me she doesn't give you the willies.