Benson to Eli Stone

Soap's Benson DuBois spunoff on to his own show, Benson

Maggie Gallagher from Hanging In crossed over onto Soap

Hanging In (and Maude's) Maggie Gallagher crossed over onto Soap for 10 episode

The first All in the Family spinoff character was Maude. Maude was Edith Bunker's cousin.

The Jeffersons' George Jefferson was the second All in the Family supporting character to spinoff onto his own show.

George Jefferson gets help from Barney Collier from Mission Impossible

Mission: Impossible was continued 22 years later

Diagnosis Murder's Doctor Jesse Travis's father is a spy that someone is trying to kill. One of the possible suspects is the original Mission: Impossible's Cinnamon Carter.

The airplane that crashed and strand the cast of Lost was Oceanic Airlines Flight 815 also featured on Diagnosis Murder.

Charlie from Lost was in a band named Driveshaft. Alias? Sydney threw a party and the music playing at the party was Driveshaft song. Additionally Alias also mentions Oceanic Airlines and so it has crossed with both Lost directly and also all the shows which mention Oceanic.

The Credit Dauphine Bank from Alias also exists on Eli Stone