I've seen a video of Howard Marks smoking with some rastafari's in Jamaica and when they would hit it, literally as they were inhaling it they would exhale through their nose. It ends up looking really cool, I guess they knew that the smoke didn't need to be held in for long periods of time.

It also pisses me off when people say others are wasting smoke when exhaling after 3-5 seconds. They really don't know what they are talking about but think they do which makes it even worse.