You want to blow, not suck in these situations.
Go to your nearest office supply store, and pick up a couple cans of compressed air. Use those to blow some gusts into the vents of systems to dislodge any dust bunnies.
Granted all this does is just move the dust from one place to another, but if you can get it OUT of your consoles, then you can use regular dusting methods to clean it up elsewhere.
I don't know if this is the right place to post this, but I didn't see a suitable forum for this kind of thread, so I'll go for it anyways. I'm looking for a handheld vaccum to keep my entertainment center dust-free, but mostly to get rid of the dust that's clogging up my consoles. My PS3 in particurlar is making a rather alarming noise, and I'd like to do something about it before it gets any worse.
The problem is that I don't want to scratch my consoles while vacuuming over the vents, so I'm wondering if there are any handheld vacuums with a soft tip out there, or if handheld vacuums come with some sort of attachment to prevent furniture and electronics from getting scratched or damaged.