Kickball is so much fun because, to be frank, there is really not that much skill involved. Since you probably played it as a kid, I'm sure you remember all the rules - it is similar to baseball.
You had so much fun playing when you were in elementary school, but when you play as an adult; it's even more fun because you feel you are back in elementary school. Plus, all that running around helps release stress, gives your brain a break, works your heart and your muscles too. It's a great way to be active and social, and get a little fitness along the way.
Fit's Tips: You can get a bunch of your co-workers or buddies together for a fun, friendly game in the park. Or if you're really into it, check out the World Adult Kickball Association (yes - there is such a thing) and find a local division to join in your state. Don't forget to have some serious fun.
Check out Adam Sandler playing a not-so-friendly game of kickball in the movie Billy Madison.