A vibroblade is a blade that vibrates very quickly. No, not like that, you sick, sick person. It is often thought of as green, but that's just a misconception.
A nasty looking bladed object, which if you get poked with, you're liable to looking at your digestive tract decorating the floor, before wondering why you have a sort of empty feeling in your middle.
However, it could stop a lightsaber (the writers needed SOMETHING that jedi don't use that can stop a lightsaber), Allegedly. No-one has been suicidal enough to try it (except for people in KOTOR, but they can survive hits from a lightsaber, strange buggers that they are.). Oh, plus don't poke anything electrical with it. It can explode, and take off your arm (and maybe your face). And you won't get a cool suit like Darth Vader, as there was only one made for Darth Fellatio, and we all saw Vader's reaction to that.