It seems that the rendition of Hatsune Miku I touched upon previously was only the tip of the iceberg; 3Dカスタム少女 / 3D Custom Girl threatens to unleash a torrent of creativity with its custom character design features, and the first sign of this is this enormous compendium of anime and game characters who have been (in some cases extremely well) created in the game and now offer all manner of erotic potential in actual play.
I have reproduced a sample below, but even more are available at the site in question, and you can of course download them for your own use, should you have the game.
I think rather more interesting than the game itself is the possibility of doing for amateur anime animation what Vocaloid did for amateur music creation – in this case the need for art skills are replaced, rather than the need for a singer. Perhaps they will see fit to spin the game off into character design/animation studio software? It might have great potential.