DonkeyKong

Play the classic old school arcade game of Donkey Kong right in your Mac OS X Dashboard.
The game is quite simple to figure out.

Move Mario left and right on the girders, up and down the ladders and avoid any obstacles in the way (either by jumping over them, smashing them with the hammer, or going around them). The arcade games consists of 4 different boards, which you play in a different order (depending on what level you are on).