By the way, anybody who thinks "Oh, it's a CMOS chip, it must be crap." should forget anything they've heard about CCD vs CMOS with regards to noise.
IIRC, Canon has been working on their CMOS imaging chips since the 80s.
Have a look at the reviews of the Canon digital SLRs at
www.dpreview.com and look at the long exposures e.g. 15 minutes for one of the 1D reviews. Mind you, the 1D costs as much as a small car
Here are 5 minute exposures with the 20D
http://www.dpreview.com/reviews/canoneos20d/page21.asp
Canon DSLRs rock. When I finish uni I'll be getting one. In the mean time, my Canon G3 isn't too bad but it's too noisy at high sensitivities (ISOs) and long exposures (15 seconds max).