Somehow, I made it this far in life never having played Tri-Ominos until today. I saw it a lot when I was a kid, and I've had this set around for ages, but we never played. It's a really good game, too. I like that you can just play it simply, or you can make use of the fairly complex scoring system for more competitive play. It reminds me, I tried to make a card game with wedge shaped cards that you formed into circles of eight cards... but I could never come up with any kind of mechanic that was really any fun. Maybe I just need new perspective on it.
Anyway, Tri-Ominos rocks -- I'm surprised more hasn't been done with it.