Imagine a bracelet or watch that changes into something else when you take it off. Perhaps it becomes a cell phone, or laptop computer. Although this scenario may seem like science fiction, this and much more will soon become reality with a ground-breaking new technology known as claytronics.
This is part of the research area called Self-reconfiguring modular robotics. You can find more info on wikipedia
I also have a blog and a podcast focusing on the area, if you are interested,
www.flexibilityenvelope.com , http://itc.conversationsnetwork.org/series/flexible.html
and http://twitter.com/#!/Perblog/ is me on Twitter. I focus on SRCMR there too!