Cable systems in central NJ carry most of the NYC and Philly channels. Not bad having market #1 and #5 on the same cable system.
Mercer County gets all NY and all Philly, but only Philly HD since its Philly DMA. Comcast in Ocean County has moved KYW 3 and WCAU 10 to digital only and carries all NY and NY HD.
In Carbon County, PA which is the Poconos area they get Scranton, and a mix of New York and Philadelphia, with all 3 Fox affiliates.
In Allentown, Service Electric carries ABC from Philly & Scranton, NBC from Philly and NY, and Fox from Philly and NY, WPIX, WWOR, only 1 CBS (KYW) though, the other Philly stations as its within DMA, but they do carry
HD feeds of the out of market New York stations as well.
As far as getting 3 of one network (excluding PBS), its harder to find though.
Along w/ Carbon County getting 3 Fox stations,
Comcast in Frederick, MD carries 3 NBC stations: WRC 4, WBAL 11 and WHAG 25. I think OTA is possible to get WGAL 8 also. They might as well throw it in the lineup as well.