The best thing about the Star Trek: The Next Generation Blu-rays isn't the improved video quality, it's this second renaissance that the series seems to be having. Suddenly, the actors are coming out for interviews and we're finding out more than we thought there ever was to know. For example, a secret about the Riker beard.
Fun fact (which Jonathan Frakes mentions in the video below)—the RIker beard is the opposite TV trope of the Fonzie shark jump. A Riker beard means your show has got itself on track.
But how did the Riker beard come to be? Well, the part many of us know is that Frakes grew a beard during the writers' strike that took place between seasons one and two. But what you might not know is that it was Gene Roddenberry himself who felt it should stick around. Despite rumors that Frakes had gotten too overweight to stay clean-shaven, Gene actually said, "Jonathan, I love the beard. It'll be nautical. We'll shape it and, that way, it'll be decorative."
Check out the video below. The beard stuff starts around the 1:45 mark, but stick around for the whole thing. There's some other great stories, too, and Frakes' Roddenberry impression is BRILLIANT.