I'm a big fan of this blower for cleaning electronics- it's safe to use, comes with a number of handy micro attachments, and costs 1/4 the 3m kit that was linked earlier. It's very powerful.
http://www.amazon.com/Metro-Vacuum-ED500-500-Watt-Electric/dp/B001J4ZOAW/ref=pd_cp_e_3
http://www.amazon.com/Metro-Vacuum-ED500-500-Watt-Electric/dp/B001J4ZOAW/ref=pd_cp_e_3
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