Via IndieGames:

Excellent news! The demo for Crayon Physics Deluxe is now available (for WinXP and Vista) for download. This is the physics sandbox game I discussed earlier.

18 levels are available to play, and while these first levels might be a bit easy, there is lots of scope for finding multiple solutions for them. The look and feel of the game is very nice, even encouraging you to doodle in the level choice screen.