I'm not sure how to have fun

I've been told that before, but it came up again because it's my birthday, my original plans fell through, and I haven't figured out what to do. I thought about going to a movie like I did last year (Monsters vs. Aliens in 3D; I loved it), but didn't see anything at the regular cinemas, dollar theatres, or art places that I liked. Today's the opening day at Keeneland, which I've never been to, even after living in this town for twenty-six years (Gods, has it been that long? Since 1984?), but it'll be packed between being opening day and the beautiful weather, and besides, part of opening day at Keeneland is being seen in your finery. I don't really have finery. :) My friends called earlier to wish me a happy birthday (one sang, beautifully) and the other suggested I go bungee jumping sometime before I die. Um...no. So what do you consider fun? What should I do?