I got a 50W laser pen off ebay. It was under £6 (i.e. under circa $12). I need one once every blue moon for lecturing work and this will fulfil the job perfectly - the light is bright enough to be seen, the pen is compact, etc, etc. Anyhow I got an email from a prospective ebay buyer - does this pen burst balloons. light matches, etc? If not then, according to this buyer, it can't be a true 50W pen. Out of curiosity, I tried to light a match with it and couldn't. Physics ain't my strongpoint - should all 50W lasers be able to do this? [Beyond intellectual curiosity, I'm personally not bothered - all I wanted was a green laser pointer and that's what I got; its strength is of zilch interest (in fact, I wouldn't want something that could generate that much heat for use in front of an audience)].