Exactly the things, I'd argue, that you can't find elsewhere in Florida, a state that has become, more or less, one enormous, anonymous, interchangeable strip mall. Celebration is like the traditional towns and villages of New England, which are, let's not forget, places we still value highly. Nantucket, in fact, is one of seven American towns whose names are displayed in the rotunda of the Visitor's Center, the way libraries used to display the names of great authors. As with these exemplars, Celebration's buildings are fairly tightly clustered. Consequently, you can get almost anywhere by walking.
Different uses tend to be mixed on the same block, sometimes in the same building.
They're not zoned into shopping here, offices there, and housing somewhere else, linked only by highways. Older folks walk downtown from their homes to sit by the lake in the sun. You run into your neighbors by accident face to face, every day, instead of passing them in cars like ships at sea.