This has to be my favourite game on the the Wii and i got it from  WiiWare.  It’s produced by a small team and is proof that you do not need millions  to create a compelling game.

There are more than four worlds, each housing  unique stages and varying objectives around using the  strengths and weaknesses of the goo balls. Its easy to get going and before you know it you won’t be able to put the Wiii controller down as you strive to get your goo balls to the exit pipe.  Since all of the goo balls have realistic physics, if you don’t build  thoughtfully and with respect to gravity, they will all fall to the ground.

The game is also availble of Mac and PC, so take a look as 2DBoy.