If I am allowed to combine various versions of tetris then easily that. I used to use it as something to keep my hands busy and can play it while maintaining enough concentration on lessons, TV shows/films (even with subtitles towards the end) and the like.
As far as actively played... possibly Perfect Dark on the N64. We used to play it when we got back in the evenings or before we went out.
Failing that various MX vs ATV games. It was more active than tetris but for the most part its free roam modes were almost meditative.
AbyssalMonkey said:
I don't believe anybody with a birthdate of earlier than 1990 who says they hadn't sunk an obscene amount of time into WoW.
You underestimate how much of a cheap bastard I am. My time with world of warcraft was a couple of afternoons and evenings on a third party server (2x exp if memory serves) when we were looking for a local co-op game before we decided it was not as good as the older co-op games and went back to one of the dungeon crawlers or something.