Thinking about this more, I think a nice big loose footed, square rigged sail on the front would work well for a starter. It would obviously only be a down wind rig, but it would be a nice, safe-ish way to start, and keep your deck nice and free. Add a few cannons, and you got yourself a themed party boat!
Small sail on each corner?! I actually like that idea, interesting! Could work down wind (wing and wing style) or broad reaching. Hmm...
I think we are straying into Bolger design territory here. There was a brilliant designer doing odd and crazy things that actually worked. If you want some inspiration for alternative boat designs, take a look at his work. Here are a few links with some pics, you can google him to find more, plans, and books.
Phil Bolger - Wikipedia, the free encyclopedia
I've seen a boat like the Indian Summer linked to above, now there's a boat that makes you go "huh?" when you see it in person. But the owners absolutely loved it.