There's a history of punk bands, death metal and also grindcore bands choosing ridiculously offensive and silly names for their bands. A perfectly offensive example is Anal Cunt, the American grindcore band whose persona and lyrical content does everything it can to offend.
There are a lot of bands out there that have also made the decision to give themselves as offensive name as they can come up with. Some are done for outright shock value, others have a sense of fun about them. I was recently reading through a massive list of such bands, and some of them genuinely made me snigger out-loud at their down-right tongue-in-cheek swaggering bravado.
As with Anal Cunt, the rear-end seems to be a popular motif for a band name. With the likes of American grindcore band Anal Blast and Peruvian (yes Peruvian) death metal band Anal Vomit. But the one that makes me snigger is the Belgium folk/goth/darkwave band Kiss The Anus Of The Black Cat! What were they on when they came up with that one? Sticking round the back for a minute, faecal matter is also a popular theme for band names. Bathtub Shitter from Osaka Japan is one that did make me chuckle, but I want a T-shirt from the Brazilian gore band I Shit On Your Face.
Coming round the front, so to speak, genitalia is an obvious theme for bands attempting to offend. There's a least 3 bands that have called themselves The Clits, and there is Cunts, using little or no imagination. However when it comes to male genitalia, male dominated bands seem to have a more irreverent take on names. From Cheap Knob Gags to Broken Penis Orchestra, via the great name of LA horror punk band Penis Flytrap. My favourite (and I am bias here) is Gobble And The Cocks, a punk band from my home town of Hull. Often shortened to GATC, being the letters used for the nucleotides that make up DNA. The story goes that once a journalist asked them what GATC stood for and they said Gobble And The Cocks as a joke, the name stuck!