Been a while since I got addicted to an interweb game. I've spent far too long today playing...
http://fantasticcontraption.com/Great little physics puzzle game thing. You build machines out of stuff to get other stuff across levels. There's a tutorial to show you what to do.
I've done levels 1 - 13.
Here's my current maddening attempt at one I haven't managed yet...
http://FantasticContraption.com/?designId=290499Argh 3/4 balls. the bastards.