I always cringe when "King Baby", the CSI episode about an AB, comes on. It's disappointing that AB portrayals are always so over-the-top. Let's not forget about the astronaut who drove across the country wearing a diaper to kill another woman. Except I think I read somewhere that she actually didn't wear a diaper, but it doesn't matter. Everyone still knows that case as "the astronaut who drove halfway across the country wearing a diaper."
I wish we weren't always portrayed so negatively, but I have to admit I'd probably laugh at us too if I saw it as an outsider.
Let's see...I can't think of any specific AB/DL references, but there was an episode of the show "Everybody Hates Chris" where one character decided he wanted to be an astronaut when he grew up, and to practice he wore and used a diaper. "Eternal Sunshine of the Spotless Mind" has a scene where one character tries to take himself and his girlfriend back to a memory of when he was about four. Although his mother sees him as a four-year-old, the girlfriend sees him as an adult wearing kiddie pajamas and talking and acting like a four-year-old. No diapers though. And the show "Family Guy" has tons of references to diapers or wetting/soiling oneself.