The object in question is a small bronze "coin" -- with a scene of sex on one side and a the Roman numeral XIIII on the other. Assuming that it is genuine (and there are quite a few fakes of these circulating and this one was not actually found in an archaeological context), then it is what archaeologists term a "spintria". This is a Latin word for male prostitute... but it is an entirely modern practice to apply it to these little objects; we haven't got the foggiest clue what the Romans called them... or (despite what you read) what they used them for. Quite a few have been found across the Roman world (there's another on the right).

Fantastic article by Mary Beard about the bronze coin recently discovered that tabloids are calling a "Roman Brothel Token." The reality is unfortunately somewhat less sexy:

More likely, if you ask me (and as the curator at the Museum of London concedes it might be so), is that it is a gaming token, for one of the many Roman board games... whose rules and customs were anyway shot through with sex (the best throw of the Roman dice was called a "Venus throw"). This belonged, in other words, on a board in a Roman bar, not in a brothel.

The trouble is that we just want the Romans to take us into the world of their brothels, and we want vicariously to enjoy their wicked sex lives. Though, in this case, there has been a politically correct, early 21st century twist added to the tale. After ogling at the Romans for a bit, many of the eager journalists (prompted by the Museum of London) have finally chosen to spare half a thought for the victims of the ancient sex industry. Don't forget, insisted the curator (correctly), that many prostitutes would be slaves. "It has resonance with modern-day London because people are still being sold into the sex trade."

The entire post is worth reading, as is Beard's blog about our modern perceptions and assumptions about the "ancient" world.