I saw Gwar at Riot Fest this summer and despite the crazy out of season cold and rain it was a great show. We recently were at a Hard Rock Casino and they had their signed guitar. I laughed my butt off imagining how random folks passing through that display (it was right next to the Monkees, for God's sakes) might look a bit puzzled... who the hell are those guys? As Dan pointed out this was before front man Oderus passed on to the great beyond.
If you get a chance to see Gwar, take em' up on it. Just don't stand too close unless you want to want to get sprayed with nasty fake blood.