We saw that when he (Tom Riker) appeared in DS9 Oh, and Beard! At least up until Insurrection - I thought he actually looked better without it by that point (ie, more "well groomed")
Back in the old days when StarTrek.com had a RP room called the Holosuite, a buddy of mine played Riker and so entrenched was the beard on the group consciousness, the immediate nickname was The Bearded Wonder or just plain ol' Beardy.