iSteal
I've taken the bus the bus enough times to know that every fifth twelve to fourty year old that you run into will have some sort of music playing device on them that also has some way of taking notes or messages and that's when I came up with the iSteal. I'm pretty sure the concept is illegal but what it is is an mp3 player that has absolutely no music on it - what it does is lift music from people around you. The player will obviously have a size limit but it takes a few songs from each playlist you get into a certain distance from and removes the oldest songs on the list so you have fresh new music all the time! Yeah!
So, I just told my sister about this idea and she said it was invasive. I said shut up. Then thought it over again. Still doing it. But now I'm a badass pirate.