If the B&D vac had a reverse it would be ideal. But this pump is working out pretty well. I blew off the loose dust that was on the back of my stereo for the last 10 years. Just a little area in the back where the bottom unit is deeper than the one on top. All wires in the way. Wicked pain to pull the stuff off by yourself. This gets the loose dust. My desk is the cleanest it's been in a long time. The only way to get all of it would be to clear the desk and wipe with paper towels and Windex or something similar.
Big improvement. Now I just have to figure out how the get the dust off of hundreds of CD cases without wiping each one individually.
edit: another good use I found for the pump. TV screen is not really dirty since I Windexed it a couple weeks ago. But it has collected a bit of dust. A quick blow off with the pump saves me getting out the spray bottle and paper towels.