Mouse House: I had to hit Orlando for the day job so I added in an extra day to troll around a bit in the mouse house. I like Disney, so you won't get any commercialism-is-the-death-of-all-that-is-good-and-worthy rants from me.
Obviously, the place is almost exclusively designed for families, rugrats in particular, so there wasn't all that much for me to do on my own, but I was situated right across from Downtown Disney, which contains Pleasure Island which is the closest thing to a place for adults. (Despite the tawdry name it is fine for kids, just geared towards adults.) There are some 18+ dance clubs, but I can't really recommend them.
One spot I can recommend is the Adventurers Club. It's themed after an a sort of African or East Indian explorers club from the heyday of the British Empire, sort of like where you'd expect to stumble across Alan Quartermain sipping a gin and tonic and hiring coolies for his next expedition. The staff is all in costume and in character. They put on little skits and engage in banter with the crowd. Good drinks. It's just bawdy enough to be interesting for adults without any possible offense to any children within earshot. Recommended.
The only theme park that is remotely suited for adults is Epcot. I caught the shuttle over and spent a longish afternoon wandering through the cultural exhibits. There's some good food to be had and there are genuinely interesting little performances that go on throughout the day. Mexico has one of the coolest looking restaurants set up like a deep dark jungle with a volcano in the background. There was a great film on China -- shown in a round theatre with 360 degree screens. The Canadian section had a rock band that featured a bagpiper. Not exactly sure how Canadian that was, but they weren't bad.
All this is set around a sizeable lake; and of course, it's Florida so the winter weather is perfect -- especially to someone from Michigan.
So it turns out a grown up can do OK in the mouse house for a couple of days. But it's still Disney, which means it is still way too expensive. These pics are free:
Epcot Lake (~265k)
Fake Morrocco (~420k)
Fake Pyramids (~265k)
Epcot Garden (~420k)