Beards
When I was flying in Europe I had a full beard. It was cool not having to shave everyday. The O2 mask fit just fine because, if you look at where it fits your face, the seal goes just under your bottom lip where there is not much hair anyway.
The other day I saw one of my Alaska Airlines colleagues with a full beard! I did not ask him about it but the guy sitting next to me said he had permission for some kind of medical problem. Huh. Do you guys know of any other pilots out there with beards?