Forget those expensive little cans of ozone depleting petrochemicals if you need a lot of compressed air. For the cost of a few cases of these wannabees, you can own your very own air compressor! You can quite effectively blow the dust out of your dinky little CPU Fan, and do much, much more with the almost unlimited supply of compressed air a compressor will provide. Of course the wife won't let you keep it in your home office, but who cares! Just keep it in the basement or garage, put a drier on it, and run a small air line to the office!
Here are a few neat things you can do with all that compressed air:
Flat Tire? No Problemo! An air compressor will refill it in a jiffy. You can even buy your own tire changing machine on Ebay and run it off the extra air. While you are at it, get an air powered impact wrench and make short work of those rusty lugnuts. A must for any at least half-serious mechanic
Got a rusty iron railing, bumper, or tractor than needs repainting? Blast the rust away with a sandblasting attachment, then use your spray gun to do a better and cheaper repainting job than a spray bomb ever could!
Roof need new shingles? An air nailer will make you wonder why you ever bothered with a hammer.
Gotta cut a few bundles of rebar? An air-powered die grinder will cut through it like butter
Guests staying overnight? Why make yourself dizzy trying to blow up the air mattress with your lungs. Need I say more?
Of course, I have not even scratched the surface of industrial uses of compressed air. Let me say that I know of factories in this area that have compressors that are run by motors in the hundreds of horsepower.
If you are out of ideas for my Christmas present, a quick walk through the air tools section of any Home Depot or Lowes should refresh your supply of ideas.