The Ancient Graffiti Project is a website that provides a search engine for locating and studying graffiti of the early Roman empire from the cities of Pompeii and Herculaneum.
The search engine allows three different types of searches:
You can search for graffiti by location, selecting either the pull-down menu, or by clicking on the map, or
You can search specifically for graffiti drawings by choosing the class of drawing that interests you, or
You can search for a specific word or phrase and find where it occurs within the ancient city.
Explore this resource at http://ancientgraffiti.wlu.edu