Boards
Magic tricks.
I love magic tricks. It's a bit childish, yes, and of course can be a bit theatrical ofc, but it's always fun seeing something which you can't explain. Like trying to solve a really hard puzzle.
I saw this the other week, it's from Penn and Teller's Fool Us, and thought it was mint. No idea (even P&T afterwards are like 'well we know some but wtf, man')
http://www.youtube.com/watch?v=nMkhC37HqvU
NOW U
Also, old as hell but Cups and Balls routines are amazing.