K9 and Company to Silver Spoons

K9 and Company was a pilot for a spin-off aired as a one-off episode broadcast as a Christmas Special in 1981 - featuring The Doctor's old companions K9 - the robot dog - and Sarah Jane Smith.

The TARDIS from Doctor Who appears in the hangar bay of the Red Dwarf - it can be seen during the launch of Starbug in the episode "Thanks for the Memory"

In the Red Dwarf episode "Psirens", the crew of the Red Dwarf come across a space ship graveyard which includes a Weyland-Utani ship, connecting it with Angel.

John Larroquette Show referenced Yoyodyne. Yoyodyne was also a client of Angel's Wolfram & Hart.

John Larroquette Show's John Hemingway called into Fraiser's show

Fraiser's Niles and Daphne read Caroline in the City's comic strip.

Caroline in the City's Caroline wished The Single Guy's Jonathan good luck

Friends was affected by the blackout created by Mad About You's Jamie on Blackout Thursday.

Mad About You's Paul did a documentary narrated by The Dick Van Dyke Show's Alan Brady.

Sally Rogers from The Dick Van Dyke Show was on Hi Honey, I'm Home!

Hello Larry's characters were mentioned on Hi Honey, I'm Home!.

Hello Larry's Larry Alder crossed over onto Diff'rent Strokes for 3 different 2-part episodes

Diff'rent Strokes' Arnold did a story for his school newspaper on Silver Spoons' Ricky.