Bones to Millennium
3 connections
Bones
CSI: Crime Scene Investigators
An episode of Bones has a reference to a prostitute who worked at the (fictional and from the CSI universe) Tangiers hotel.
The X-Files
Morley cigarettes are smoked by Warrick Brown in a episode of Crime Scene Investigation.
Millennium
The X-Files' Jose Chung was also investigated by Millennium's Frank Black and later X-Files' Mulder and Scully meet Millennium's Frank Black.