actully talking about TV Universes NBC has a big Universe in the late 90's that all existed in the same universe.
-Mad About You
-Seinfeld
-Friends
-Single Guy
-Caroline in The City
-Newsradio
-OZ (based on the Seinfeld OZ SNL skit)
All exist in the same universe. not sure if ER exists in it as well.
Of course they also had the Cheers universe which actully includes:
Cheers
Frasier
WINGS
Simpsons (based on the episode Homer went to Cheers)
Family Guy
I'm sure Cheers exists in the same universe as Freinds and those shows and if we could tie those together with Fresh prince or Jeffersons that would mean almost every great show exists in the same universe. Except for Curb. But as far as i'm concerned if Ryan O'reily ever escapes oZ and gets into the cuy he'll take Rachel hostage!
In the UK, the BBC comedy "Last of the Summer Wine" has been running since 1973, with two of the three main characters played by the same actors since then. The last series was in 2001, I believe.
Of course, being a UK show, it has a lot less episodes than a similiarly long running US show.
"people" as in characters, or people as in actor/actress? I don't see how an actor appearing in two different shows "links" the shows' universes. I mean, taking it to its logic conclusion with the 6 Degrees of Bacon game, and everything is connected. So what?
People as in characters. If a character from one programme appears in another programme as that character, then they are together in the same universe.
Here is an partial example from the list of shows in post 25 - The X-Files has an episode where the Lone Gunmen meet Detective Munch from Homicide: Life On The Street. After Homicide is cancelled, the character of Detective Munch moves to L&O:SVU, and The Lone Gunmen TV series is also later created. Therefore, The X-Files, Lone Gunmen, Homicide, and all the various L&O shows exist in one universe. If you work through other similar crossovers, you'll find similar connections to the shows listed.
About the Munch/X-files thing don't forget that Mulder and Scully were on The Simpsons so that means all those shows exist in the Simpsons-Cheers universe. Plus if you consider we never saw the person thatt attacked Ernest Borgnine and the junior campers at the end of an episode of The simpsons but heard the "chiii-chaa" sound we can sorta conclude that it was jason and since jason had the necronmicon in Jason goes to hell that means that Evil Dead, Simpsons and Homicide all exist within the same universe.
And we can't forget that archie and his gang once beat up Homer and since Archie met The Punisher and the Ninja Turtles in his comic that means all these shows are actully taknig place in the Marvel Comics Universe!
Plus Newsradio also had an ending where an autistic boy was dreaming of their world so if you can connect Newsradio and the Seinfeld universe to St.Elsewear that confirms that almost every TV show ever made was dreamt up by that boy.
The rest were dreamed up by Buffy. Which would expalin Alias.