I ate at Olive Garden the other day, and I saw a waiter with a waist length pony tail!
It looked in pretty good condition from where I was surreptitiously peeping (I didn't think it would be appropriate for me to bounce over to him in front of my coworkers and interrogate/compliment him about his hair).
Looked to be light toffee brown with gold streaks, with only a slight wave.
Aside from being eye-catching, he didn't look unprofessional at all, either.