There are several nerd stereotypes out there. One of the more recent ones is karate. At the basest level, it makes sense. Learn to defend yourself from the asshole taking your lunch money. And any fascination with Asian culture brought on by video games probably doesn't hurt either.
Can't say for sure how relevant any of that is anymore. But, to note, my instructor is a math professor here at the college, and a good number of us in the class are math or science majors of one kind or another.
I do Chidokwan style, and have just finished my third semester of it by successfully testing for my green belt this evening. We've had our share of traditional kata (Heian Nidan & Heian Sandan), arnis sticks and throws, but also a good number of practical self-defense techniques.
So, if you do martial arts, what kind? And for those who don't, what do you think about the stereotype today?