They do hemispherectomies now-a-days (first at Johns Hopkins, now all over) for sever, debilitating epilepsy. Children with frequent life-threatening seizures that don't respond well to medication undergo functional hemispherectomy, where nearly all of one hemisphere is removed, not unlike with this young man.

wikipedia? sure... http://en.wikipedia.org/wiki/Hemispherectomy

... and at choggie's comment, I understand the downvote for voyeurism, but I was astounded the first time I heard about the hemispherectomy procedure, and thought this video was similarly astounding ... he literally had much of his brains blown out and is still a high functioning person... if you asked any Joe Nobody on the street if you can live with half a brain they might just say "a'course not!", making this a pretty interesting clip.