We Are SEX BOB-OMB (Fast)
By: Beck Hansen
This "fast" version of the song is available on Nigel Godrich's Original Score for the film. The score is available for purchase from iTunes.
This take of the song is instrumental and is credited to "Beck & Nigel Godrich." I reckon Nigel just remixed it for a scene in the movie.
I also believe that this was what Beck originally wrote for the soundtrack, but then it later got stretched and a verse was added so the band could sing on it (which can be heard on the soundtrack).