With the advent of 3D Dot Game Heroes I was in the mood to make some of my favorite old game sprites into retro style 3D creations. It just so happens that there is a sick FREE online tool that lets you do just that. Its called Q-Block and its a blast to play with. There are tons of user created pieces that you can view in 3D space and edit at will. The editor is crazy easy to use. You basically just have to build your stuff like you would in 2D with a program like MS Paint or Pixen but it has layers allowing you to build objects with depth. You can also just click in 3D space to attach new blocks or take some away. Here is a Darknut from the original The Legend of Zelda that I threw together.
As fun as building the stuff is, the real kicker is that you can have your creations printed on stuff for you like T-Shirts, mugs or even dog sweaters... if your THAT kind of person. You can also download them as wallpapers or animated GIFs.
So seriously, go check it out.