Techlab St Joost documents the brains for their speaking t-shirt on instructables:
A t-shirt with conductive ink, that can make a sound when you push it.
Every Wednesday is Wearable Wednesday here at Adafruit! We’re bringing you the blinkiest, most fashionable, innovative, and useful wearables from around the web and in our own original projects featuring our wearable Arduino-compatible platform, FLORA. Be sure to post up your wearables projects in the forums or send us a link and you might be featured here on Wearable Wednesday!