Couple of examples from the forum: http://www.therapistfinder.com/ http://molestationnursery.com/ http://www.penisland.net/ http://www.expertsexchange.com/ http://www.powergenitalia.com/ http://www.whorepresents.com/
Atleast Expert's Exchange eventually put a - in the URL. Companies are dumb, choosing a domain name is the first step towards SEO. Customers need to remember it, it needs to be relevant and easy to type. It's usually best to pick up a range of addresses anyway ".com, .net .co.uk versions etc.); it's a small price to pay for extra customers.