A time travelling double header over the weekend.
Primer (Donny Darko for grownups) made for about 7k, first shown at the Sundance Film festival, and took over 400K at the box office plus whatever it has taken on DVD. Extremely techie and I kept up with it till about 75% of the way through the film but started to get a bit confused at that point. However at the end I had a pretty good idea of what had happened even if I couldn't follow the timeline exactly. There is a good Wiki on it though and excellent directors commentary as well on the DVD if you really want to get into hiper-nerd mode

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Source Code Jake Gyllenhaal of Donnie Darko fame gets back into time travel with a film that is a sort of a cross between the films Groundhog Day and Deja Vu. Much easier to follow than Primer and has the high production values you would expect on a bigger budget film. All the time travel bits had been covered before though.
Both excellent films but Primer offered something a little different in the time travel genre.