ER (1994) to The Adventures of Superman

A reporter on Chicago Hope talked to Dr. Austin about having been accepted into the space program and mentions an ER doctor from County was also accepted. In a separate episode of ER Dr. Greene was accepted in the space program.

Chicago Hope's Jeffrey Geiger accepted an organ of a victim on Homicide. Also St. Elsewhere's Dr. Craig won the (fictional)

St Elsewhere's Westphall, Craig and Auschlander visited Cheers' bar

Cheers spun-off Frasier

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.

The Dick Van Dyke Shows' Buddy appeared in an episode of The Danny Thomas Show

The Danny Thomas Show's Williams family shares a home (briefly) with the Ricardo family on The Lucy-Desi Comedy Hour in 1958, the next year the Ricardo family returned the favor and visited the Williams' on The Danny Thomas Show.

The Lucy-Desi Comedy Hour was a reworking of I Love Lucy

Adventures of Superman's Superman visited Ricky Ricardo on his birthday in an episode of I Love Lucy.