Here is a video about a modification to my shop vac that I did a while ago. What I am doing is essentially making the canister over an order of magnitude bigger by using a steel garbage can as the canister. As a bonus, when it is time to take out the sawdust to the curb, I no-longer have to dump the canister into a garbage can since it is already in a garbage can and is ready to go out to the road for pickup.