The Everglades is one of the largest wetland areas in the world, and in this particular Natural Park you can see alligators, crocodiles (saltwater), flamingos, and a large number of insects and birds in their natural habitat. The fact that you can only go by airboat or on one of the few roads makes it a must-see wild place in South Florida. Watch out for the summer months season because of the large number of hungry mosquitoes that will suck you dry. It is best to visit between January and May, because the temperature is mild and there are no mosquitoes, which really are a nuisance. Due to the massive dimensions of the park and the restrictions to visiting it, it is best to hire a tour of the park, or plan out your visit really well by renting an airboat and visiting some of the observation sites that are available.
Last year I was fortunate enough to attend a private Ferrari race called "The Ferrari Challenge", organized by the U.S. Ferrari dealer. It's basically a bunch of people with a lot of money that lease giant race tracks to do some laps in a Ferrari 430. Since it was a private event, I was able to move around the speedway freely and see all the pits. It was really spectacular. In Homestead, Miami, there are NASCAR races and Formula Indy (my father was there in 2007 for the NASCAR). Here are some photos of the event.