You can plug your laptop in like this dude...although it looks like he is up to something! This project is called Dead Drops, by Aram Bartholl
‘Dead Drops’ is an anonymous, offline, peer to peer file-sharing network in public space. I am ‘injecting’ USB flash drives into walls, buildings and curbs accessable to anybody in public space. You are invited to go to these places (so far 5 in NYC) to drop or find files on a dead drop. Plug your laptop to a wall, house or pole to share your favorite files and data. Each dead drop contains a readme.txt file explaining the project. ‘Dead Drops’ is still in progress, to be continued here and in more cities. Full documentation, movie, map and ‘How to make your own dead drop’ manual coming soon!
Via Aram Bartholl Blog
Well my new Macbook Air has a USB port...will have to try this if I run across it. Seems kinda dirty to me though!