If I add one to zero I get 1, that number is odd. If I add one to that, and get two, that number is even.
If I add one to that and get three, I have a pattern, because that number is odd.
http://dl.dropbox.com/u/666516/easyspace.cap
+ MouseKeyboard: On key Space pressed
-> Sprite: Add 1 to 'num'
-+ System: Sprite.Value('num') modulo 2 Different to 0
---> Sprite: Set Y to Sprite.Y-64
-+ System: Else
---> Sprite: Set Y to Sprite.Y+64