The LilyPad Arduino is a small microcontroller board designed for wearables and e-textiles. It can be sewn to fabric with conductive thread to create interactive objects, clothes or accessories. it is washable and used to create Smart Fashion.
Links:
http://www.diylife.com/2008/04/16/pretty-lilypad-arduino-microcontroller-for-wearable-electronic-a/