Castle to Journeyman
5 connections
Castle
Law & Order
Hudson University from L&O also appears as the home of various victims and crimes in Castle,
Homicide: Life On The Street
Law and Order and Homicide crossed over on four episodes
Chicago Hope
Chicago Hope's Jeffrey Geiger accepted an organ of a victim on Homicide
Early Edition
Early Edition's Gary and Marissa went to Chicago Hope's hospital for medical treatment.
Journeyman
the characters in Journeyman read the same fictional San Francisco Chronicle that provided Gary with Early Editions.