The City to The Flash

The City spun off of Loving survivors of the Corinth Serial Killer leave Corinth to an apartment building in NY SoHo

All My Children and Loving crossed over a number of times.

All My Children and Loving feature the fictional Trans Global Airlines

Diagnosis Murder's Dr Mark Sloan was defended by Matlock when Sloan was accused of murder

Oceanic Airlines

NCIS was a spinoff of JAG

NCIS: LA was a spinoff of NCIS

NCIS: LA and Hawaii Five-O worked together in a crossover episode to stop a smallpox outbreak

Hawaii Five-O references Dominic Alonzo from Arrow

Arrow spun off The Flash