I thought it was the other way round... the Dust Brothers (of Fight Club OST fame) were originally the Chemical Brothers.
No, AlexH had it right. The Dust Brothers (of Beastie Boys' 'Paul's Boutique' production fame) were knocking away in the States in the 80s, then fell off the radar pretty heavily. It seemed to me they only came back into circulation after the now-Chems started using their name - Beck's 'Odelay', then that soundtrack you mention, plus of course Hanson's 'MM-bop' and some tunes for a requisite excuse-to-tour album from the Rolling Stones. Nifty.
I had a few singles and remixes credited to the UK Dust Brothers before the name change. Pretty sure I've sold them all, though, along with whatever else I had.
Only other names I can think of right now, beyond local cover bands and nonsense:
Shakespear's Sister (The Smiths, ignoring their typo/spelling mistake)
Scott 4 (Scott Walker)