Wouldn't those small keyboard cleaning vacums emit an EM feild (from the motor) that could damage delicate electronic parts and/or corrupt data on magneitc storage devices?
Here is something I just came up with:
If you have a canister vac, go to a supply store and buy one of those long and thin plastic attachments made for cleaning in tight spaces. Then, chop a long, maybe quarter inch wide in it to reduce the suction force and use that. You could adjust the lenght of the groove with duct tape or soemthign similar.