Bones to Person of Interest

An episode of Bones has a reference to a prostitute who worked at the (fictional and from the CSI universe) Tangiers hotel.

Morley cigarettes are smoked by Warrick Brown in a episode of Crime Scene Investigation.

Fringe makes reference to The X-Files classification of files.

In the pilot of Person of Interest John Reese's suspect Diane Hanson has emails numerous characters from Fringe