Ehh... sorry. I was sorta sued to thinking that everyone in the world knew about this.
Well, MUGEN (pronounced "Moo-gehn") is a 2d fighting engine developed by the now 'dead' elecbyte. You can change almsot any element in the game to your liking. Stages, characters, life bars, music, storyline, etc. You can create any character that you can think of, even from scratch. The characters in the videos were made by ripping the sprites, then writing batch files and such to make the characters work with the engine.
I sorta wanted this to be a Melty Blood thread.... but since everyone seems to be interesrted in Mugen, we can make it about that too. Unlike Melty Blood, i can provide links for characters and the engine itself legally (I have a torrent for melty blood, but i'm not sure if the moderators would approve of that)
So i guess... freebies soon to come....