The king of town is a character on the homestarrunner.com site run by Matt Chapman and Mike Chapman. As might seem obvious from his name, he is the 'king' of the town inhabited by Homestar, Strong Bad, and the rest, known as Free Country, USA. (thanks gousgous)
Although he lives in a castle, dresses like a king, and seems to be the only employer in town (the Poopsmith works for him, as well a crazy looking chef and some random knights), he doesn't really act like a king. For the most part he spends his time cruising for food. The KoT will eat anything in sight, as seen in just about any cartoon he has appeared in. In one Strong Bad email, he steals Strong Bad's tanning supplies (tubs of cocoa butter and animal 'phat') to guzzle down.
Although he appears more often than, say, Pom-Pom, he doesn't seem very popular or respected by his subjects, especially Strong Bad. His one major cartoon on the site features Homestar's search for the KoT's lost sheep, by the KoT's request. I won't spoil the ending, but you can probably guess it....
For a funny KoT version of the homestarrunner.com intro and menu page, check www.homestarrunner.com/kingintro.html