great idea! i am going to try this but use PVC or ABS plastic pipe to make it all happen. nice man, real nice! it works really well huh? no funky smell at all? what about smoke? all of it dissipates ?
i would say it handles moderate bong hits... and depending on how yours comes out you might have to play around with how much charcoal to use too much and the fan wont be able to pull the smoke thru the charcoal. the first one i built was with a 4 inch plexiglass tube! and a 5 inch fan.