Remember Street Fighter? Mortal Kombat? Well apparently some people got together and thought it would be a fun idea to make a game that lets you pit any character against any character, and basically a "all against all" game was created.. The cool part is, you can install as many or as little characters as you want. Heres the link:
http://randomselect.i-xcell.com/
Little warning, you should probably read the instructions so you know how to install characters. Have fun!