Set: geeky card-game that rewires your brain

Last week on a rainy afternoon in Amsterdam, I ended up playing a few hands of Set on a friend's houseboat. I'd watched the game played once before at a nerdy event, and the fiendish intensity of the players was a gigantic warning-sign -- this was a game with an event-horizon, something that would suck me in and never let me out again.

It's true: Set is amazingly addictive, a nerdy game of great fascination, one that makes your brain reel and reconfigure itself, so the whole world starts to appear Set-like after a few hours' play.

The dealer puts down twelve cards, and players hunch over them, trying to find three-card sets. For three cards to form a set, each of their attributes must either match or diverge. There are four attributes with three possible configurations each: shading (solid, outline, grey); color (blue, red, green); number (one, two, three) and shape (rectangle, oval, squiggle). It's a little like Boggle in that the winning strategy is a combination of directed searching and general unfocusing of the eyes and trusting to intuition to make the sets pop out of the well. Players are penalized for calling out false sets, which happens all the time, since once you engage the pattern-matching centers of your brain, they can't help but see phantom sets in the cards.

Play this long enough and every bit of the world around you turns into Set -- the three chairs are matched as rectangles, unmatched in color, but, darn it, shaded the same. No set. Link

Update: Here's a PalmOS version -- thanks, Kostia!