Algodoo

After testing the first entries, I realized that there wasn`t enough flat space near the blocks, the blocks had sticking issues, and perhaps some more work space was needed too. New blocks also have larger slots and are easier to stack. Black block is higher but easier to knock down.

Contest & rules can be found here:
http://www.phunland.com/forum/viewtopic.php?pid=58281#p58281