My wife got invited to the Kentucky Derby though work. I was invited to tag along (had to pay for my own flight, but that was basically it). A large insurance company had sprung for the whole deal and it was first class all the way. Not my normal hang.
But if you get the chance, I highly recommend it.
They rented out two large homes in a nice part of Louisville. Apparently lots of locals clear out for Derby weekend and make a killing renting their houses. This one was very nice.
They had a bus/limo take us to and from, with a police escort clearing the way (apparently police from nearby towns pick up extra money this way).
And at the Derby we were in the Trophy Room, which is a big room with food and open bar that opens to a large balcony overlooking the finish line.
We were there Friday for the Kentucky Oaks and Saturday for the Derby. Over 20 races over the two days. The weather was good Friday and fantastic on Saturday.
A great couple of days.