If you wanna do some fun martial art, try out Capoeira!
It is absolutely awesome, you mix kicks and foot techniques with acrobatics, music and rythm.
I liked it, because even if you are a beginner you wont get beaten up, most of the moves are with your legs, and its more of an action-reaction game. You evade and dodge mostly, not stopping kicks. And if you dont believe its useful, yes, ive seen the top guy in my class, who was about 2 meters and quite muscular flying out above my fkin head about one and a half meters away... the master asked him ( who is barely 160 cm) if he wants it faster a bit than what speed he plays with us. Well... that was epic ownage imo
If you dont like it, try wing chun... you can see the movie Ip-man about it. one of the most disciplined martial art out.