This year, for the tenth anniversary of the TV Crossover Hall of Fame here at Toobworld Central, we're inducting new members every week, rather than just once a month. And one of the scheduled inductees for March gained an added bonus to his resume of qualifying appearances in the TV Universe. And he probably didn't even know about it until the episode aired.
In the 'Eleventh Hour' episode "Eternal", Dr. Jacob Hood saw a picture of the late Lowell Parks (who was discovered to have two fully formed hearts) with three beautiful women... and Hugh Hefner.
Something not too different from this. I bet he must get bored posing with so many loverlies all the time......
Even though the founder of Playboy didn't actually appear in the episode, the photograph confirms his presence in this corner of the TV Universe. And since it shows him with a fictional character, that means he's Hef's tele-version and thus connects 'Eleventh Hour' to other shows like 'Entourage' and 'Curb Your Enthusiasm'.