The Flash to The United States of Tara
5 connections
The Flash
Arrow
Arrow spun off The Flash
Law & Order
Hudson University is the fictional University where many Law & Order characters graduated as well as the location of F.I.R.E.S.T.O.R.M. On Arrow
Homicide: Life On The Street
Law and Order and Homicide crossed over on four episodes
The X-Files
Homicide's John Munch questioned The X-Files' The Lone Gunmen.
The United States of Tara
Cheers spun-off The Tortellis with Carla.