It's clear that there are a lot of Star Wars fans these days, but one of them just took that adoration to a decidedly geeky new level. Styropyro (he of laser shotgun fame) has built a lightsaber using a heavily upgraded 7W blue laser -- it's several times more powerful than what's needed to blind someone. While the beam isn't contained like the "real" thing, it's strong enough that it can burn through wire and other household objects. You probably don't want to build this at home unless you're exceptionally careful, then.