I would like to make my B&W G3 near-silent, like my iMac. I know it's possible, but I am curious to see if anyone else on here has performed this procedure.

This guide takes the route of adding sound insulation in the form of foam padding:

http://www.xlr8yourmac.com/G4ZONE/G4_fan_noise.html

I think it would make more sense to get a new 120mm fan instead, though I've read the B&W G3 uses a 2-pin connector not the normal 3 pin.