This is a cleaned-up and expanded final version of the post I did a long time back.
THE PILOT (UNDER THE GUN)
At 1:42 you see John Vernon as the mayor of San Francisco. He also played the mayor of San Francisco in DIRTY HARRY. Plus, as far as my memory goes, he acts the same in both the movie and here.
At 5:40 to 5:52 in the backround you can see two men intended to be Crockett and Tubbs. (I never would have cought this one without the commetary)
http://www.youtube. com/watch? v=kVWpH-yHMa8
(You can fine the rest of the episodes by the links on the right hand side)
At 1:43 a man intended to be Alfred Hitchcock walks by the screen with his theme playing. Since Hitchcock cameos in all of his films, can we say all hitchcock films are in the WNU by this crossover?
http://www.youtube. com/watch? v=APAOp41UNro
(You can find the rest of the episode by the links on the right hand side)
PLAY IT AGAIN SLEDGE
Due to the large ammount of crossovers here I'll be doing this one in parts.
At 3:10 a man who looks a lot like Humphrey Bogart shows up. Who he is, and why he matters to us, is explaned at the end of part three.
At 6:08 the man mentions Richard Diamond, Sam Spade, and Philip Marlowe as if they were real people.
At 6:49 in the backround are a pair I'm quite sure We've seen before. As to how they can still be alive...I'll leave to someone else.
At 7:30 (with a much clearer shot at 7:52) the Maltese Falcon can be seen. Now, since when we last saw the real one it was in a shark's mouth, how does it get into Sledge's office? While we could call it one of the fake ones from the novel, what would be the fun in that?
http://www.youtube. com/watch? v=em0OanhRwP0
At 4:00 Sledge Mentions "That limey jerk" and seems very personal about it. As if Sledge and Bond met in the past and that meeting didn't go too well...
http://www.youtube. com/watch? v=JvmRvrPXtR4& feature=related
At 3:54 the man mentions Diamond, Spade and Marlowe again. This time with the added statement that he is not any of the three detectives. (or he is all of them, which clearly cannot work in the WNU.)
http://www.youtube. com/watch? v=mdNB_mpxAts& feature=related
I'm sure there are many more crossovers in Sledge Hammer. But I think this is enough to get him into the Universe.