QUOTE
I use a vacuum, its ideal because its plastic and cant hold electric charges and doesent blow the dust elsewhere.
The air itself passing over the circuitry.. laden with dust, can form static charges....
not that its very likley anyway.
also.. a vac is good to get the loose stuff up.. then you gotta clean it properly, best ways i know are air can or paint brush. The paint brush will last a lot longer

i just had to strip my system, theres a lot of building work going on here.. new kitchen fitted, new bathroom.
new dust

i took my mobo out and took the fan off the top of my Zalman cooler, easier than taking the fan off the board as its a bolt on one. there was that much dust i eventually had to strip the whole lot off and clean it on a anti static foam mat on the floor... theres was just too much dust.
Heres what i found: