These are big hit at work. Works on most standard spray cans. Paint, lubricants, cleaning products. Clips right into the top of the can and you aim it and pull the trigger like a firearm. Normally you see cheap plastic stuff like this coming from China and poorly made. This one is made in the USA and I was surprised at it's better than average build quality.
http://www.cangun.com/index.htm
http://www.cangun.com/index.htm