The following is not an endorsement of Dyson vacuum cleaners. I am not thrilled with mine for numerous reasons and I think they are terribly overpriced.
However, for existing owners, I can make the following suggestion. Dyson makes (also terribly overpriced $30) a soft bristle brush. It is a long oval shape. I find it excellent for vacuuming the tops of equipment. Dust seems to want to cling to brushed aluminum. I hate the idea of "pushing" dirt around so I like the "suck it up" approach.
If there is enough clearance between shelves the brush can reach all the way to the rear. I also use it for vacuuming heat sink fins and the shelves around my equipment.
I also use the Dyson to vacuum the screen on my LCD TV, computer monitor, and keyboard. I prefer the approach of lifting the leading edge a little so the vacuum gets a chance to suck up the dirt before the bristles push it around. My brush is dedicated to audio/video/computer only and I never use it for general cleaning purposes.
WARNING: Be careful around plastic. I only vacuumed the stand on my LCD TV a couple of times then I noticed many fine scratches from the brush. The stand is gloss black. Fortunately I moved the TV to the wall. The gloss black frame of the TV must be a harder composition because I do not see any scratches on it. Just beware of using the brush on plastic especially precious turntable covers.