[ohenry]

I use a Sensor Brush for most cases. When that fails to do the job, I use the method described by Mark although I use a sensor swab from Copperhill with a clean PecPad each time rather than the disposable ones.

The only thing that I'd add to Mark's comment about shooting blue sky to see the dust, I shoot at f/16 or f/22 when I do this. Maybe it doesn't make any difference, but I know that dust seems to appear more apparent in normal pictures when shot at stopped down apertures.