In the year 79 CE, a volcano named Mount Vesuvius erupted, covering the Roman city of Pompeii under a thick layer of volcanic ash and killing its inhabitants. This city lay buried, preserved for the ages until being discovered 1748. Pompeii has given us unique insight into how the ancient Romans lived and worked, due to the circumstances of its death it has been preserved very well. One thing we have learned is that Graffiti was just as common in ancient Rome as it is today. Only back then it was carved in stone.
This website has translations of much of the graffiti found on the walls of Pompeii buildings. As warning: like modern graffiti, much of this graffiti is definitely not the sort of thing you want your children reading. It contains explicit references to sex and other such things, so if you are offended by that sort of stuff you probably won't want to follow this link. But I found it terribly interesting. It proves that the ancient Romans were kind of like us.
Check it out.