I have a standard plumbers blow torch, self ignition
I use it to roast peppers, to creme brulee (but I have to be careful because the sugar will burn really fast because it's really strong), and for some stir fry.
I learned from my friend Michael to have the heat on high under the wok and then hold the blow torch in my left hand into the pan, tossing the contents of the pan with my right hand. It works great, super fast, rather fun in a pyro kind of way. Really fun when guests are over because it sort of freaks people out... heh heh
By the way, my mom gave me the blow torch. Love that...