Well LIP...you fell right into my trap! There is a point to re-inhaling the VAPORS (not smoke).
Check this out:
http://en.wikipedia.org/wiki/Vaporizer
It states:
"Interestingly, the Leiden Univsersity study [2] found that as much as 30%–40% of inhaled THC was not absorbed by the lungs and simply exhaled. However, they did not find large individual differences in the amounts exhaled."
and...
"The longer vapor is stored, the more of the THC is lost as it condenses on the surface of the vaporizer or the balloon. This loss may be negligible over a few minutes but may exceed 50% after 90 minutes"

So suck it out sooner than later. And Burnable - I'll have to try a balloon...a big-ass balloon, although the taste might be altered from the rubber.