What happens when you put cold soda into a glass and then set it on your desk for a few minutes? That's right, it sweats or forms condensation. The same holds true for your question. If you're having temperature issues with your rig, consider getting better fans or where the rig is housed. Is it on the desk or closed up in a cabinet?
Ducting the comp to the outside? Never heard of such a thing, the vision of what such a thing would do to the internal components frightens me...
I\'m already visualizing the duct tape over your mouth...