Disclaimer: I am not getting paid for informing you of this product. Obviously... haha.
I personally think this is hilarious. One day, my boyfriend started talking to me about an ingenious invention. I was hoping he was going to tell me that they finally made a device that would tell you the location of anything you lost. Unfortunately, my hopes were killed when he told me that this invention had not been made (party pooper). Instead, the ingenious invention was a notepad. A waterproof notepad.
Um... that's kinda cool, I guess? In between scrubbing and rinsing he now has the ability to write calculus notes on his waterproof notepad (the calculus notes are still there, by the way).
Here is the link for the waterproof notepad: http://www.myaquanotes.com/