Paper based encoded messages

I just wrote an opensource html/javascript page for encoding messages that can be read using only paper and a light. You can try it here:

http://rareventure.com/paper_otp/

The message is split up into two pages. Both are required to reveal the message. This can be used as a way to reveal important passwords, etc. for friends/family, in case something happens to you, by giving each of the two pages to two people you trust.

Messages are created locally on your machine and not transmitted anywhere. It uses the "one time pad" algorithm, which is provably uncrackable as long as the key used is random and never reused.