Planet June does some really cools stuff with Shrinky Dink plastic. She makes rings out of it! Supplies you'll need to make 'em is minimal and includes the following:
I really, really, really tried how to remember this cool parlor trick from my days of Klutz books for Christmas presents... I could not.
But, luckily, this cat from WikiHow knows the whole process to turn an ordinary dollar bill into a bit of bling.