I have the Metro Vacuum ED500 DataVac 500-Watt 0.75-HP Electric Duster 120 volt (linked below) and it works very well. It's a bit expensive, but depending on how much you use compressed air will be cheaper over time. Additionally, you don't have to worry about turning it upside down and destroying your components as you do with compressed air. That being said, I agree with the notion that if you don't have dust filters you should get those first.
http://www.amazon.com/Metro-Vacuum-ED500-500-Watt-Electric/dp/B001J4ZOAW/ref=sr_1_1?ie=UTF8&qid=1423710761&sr=8-1&keywords=metro+vacuum