Posted 10 December 2008 - 11:10 AM
Canned air is the best, most companies use an inert gas so that there is no chance of creating static electricity.
As rigacci has pointed out the air in the tank can contain oil, most compressed air has a by product of water, most compressors used in sensitive areas will use a dry filter.
There are small vacuum cleaners that are built specifically for the use of cleaning computer cases, I haven't seen one up close and personal yet to see how they address the static electricity problem, I suspect that a low volume of vacuum is one answer. If you are careful you can use a vacuum, just make sure that you don't touch the nozzle to anything inside the case. The problem with vacuum cleaners is that the large amount of air and dust particle traveling through the tube is a great static electricity generator.
You can use the shop vacuum to blow out the case, but I doubt that you will get enough volume to be able to blow out the heat sink and fan on the CPU.
Family and loved ones will always be a priority in my daily life. You never know when one will leave you.