At my last job I saw this device that completly encased the pc and it acted as a air purifier and got rid of any dust so it wouldn't enter the computer. I'm trying to find that again but I can't seem to find one like that. Does anyoen know the one I'm talking about or have a suggestion for a better one?

Umm...why?

Computers aren't that dust 'sensitive'...

No, but its in a very dusty area and we're very reliant on these computers. Plus, when the motherboard heats up, dust stops it from dispersing the heat as easy. right?

I was looking for that picture both Whyzman and Reid posted showing a filter setup, pressurized the case with clean air.

Found it!
http://www.overclockers.com/tips1092/