I have found industrial q-tips useful for poking around to dislodge and pick up dirt, especially desktop or tower CPU, other cooling fans, nooks and crannies. And then blast in the compressed air.
I also have a lot of little brushes of different sizes, and they, too, can be handy.
I also use a commercial screen cleaner that has the smell of some ammonia. I do not know if the company exists any more. I bought a carton of the stuff as part of an auction years ago, and I still have quite a few unused cans. The can is marked C.R.T. Cleaner, so you know how old it is, and the company is Compu-Kleen Inc.