Call Mr. 'D' to That's So Raven

In syndication early episodes of Richard Diamond, Private Detective were called Call Mr. 'D''

Richard Diamond, Private Detective's Sam reprise her role on an episode of The Dick Van Dyke Show.

Richard Diamond, Private Detective's Sam reprise her role on an episode of The Dick Van Dyke Show.

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

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

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

Cheers spun-off Frasier

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

The Bob Newhart Show's Elliot Carlin visited the psych ward at St Elsewhere's St Eligius Hospital.

The Bob Newhart Show's Bob Hartley woke up after dreaming the entire series Newhart during Newhart's finale.

Newhart's Larry, Darryl and Darryl squatted in Coach's Hayden and Christine's home

On a network crossover night, The Drew Carey Show, Grace Under Fire's Grace Kelly, Coach's Luther and Ellen's Paige and Spence all show up. Finally on Ellen, Paige and Spence run into Grace Kelly and Drew Carey

The Drew Carey Show's Mimi appeared in an episode of The Hughleys

The Hughleys crossed over with The Parkers.

The Parkers was a spinoff of Moesha

Hakeem and Niecy from Moesha went to the prom with Cher and Sean from Clueless.

Sabrina from Sabrina the Teenage Witch visited Cher from Clueless in the episode "Mr. Wright."

Sabrina the Teenage Witch also crossed over with Boy Meets World on several other occasions.

Boy Meets World was continued decades later in Girl Meets World

Austin and Ally appear on an episode of Girl Meets World. Bringing the Disney Channel Live Action Universe into the Westphall Universe

Jessie and Austin & Ally crossed over

Mr. Moseby from The Suite Life was on Jessie

That's So Raven crossed over with The Suite Life of Zack and Cody