Evertt Bradford sends in his latest update to his Pyro wrist-mounted flame cannons. They looks badass. I have only one suggestion: test these outdoors, buddy.
I saw a similar system in use by some fake firefighters at Burning Man this year, although they used back-mounted propane canisters. Everett's wrist accelerator and ignition are quite slick, though. I don't recall how the firefighters triggered theirs.
Post up plans, Everett! I want to make these for myself. Ha-do-ken!