Phrenopolis is the place where Dave goes to create other kinds of fun. There's some writing, various kinds of "art," pumpkin carving, a location-agnostic scheme for telling time, an unusual look at the solar system, and other surprises. The Maximegalomporium, at which you can buy an actual physical book, is possibly the only store on the internet which is designed to mimic an old-school text adventure (EDIT: The Maximegalomporium has closed for business, but it was kind of cool. Maybe it will make a return appearance as a library.)
Future developments that have been authorized by Phrenopolitan city planners include games, citizenship, and other cool stuff, so be sure to visit every now and then to see what's new.
While you're here, take a little time to explore the back alleys. Read some old Poems of the Week. Admire the pumpkins, and take a bit of a vacation from wherever your head and your feet normally reside.