I've become interested Contract Postal Units (CPUs), which are postal stations operated by private businesses under contract with the USPS.
My eventual goal is to publish a listing of CPUs in New York State. Currently, I have discovered at least 60 such offices based on information from the USPS website.
Although most mail is no longer postmarked by the CPUs, they do have cancelers available for document use and these are used to postmark covers if requested.
Valley Manor is a retirement community in Rochester. One of the amenities offered is that there is an office with postal services on site. Other CPU in the Rochester area are at RIT and the UofR, Strong Memorial Hospital and Lyell Video.
To emphasize again, these offices are operated by private business, NOT the USPS, but are part of the Postal System.
Ithaca College (Ithaca, NY) has its own postal station. It serves the 6500 students and 1000 faculty members.
Colgate University in Hamilton, NY serves 2700 students with a faculty of 300. The CPU is located in the O'Connor Campus Center commonly known as The Coop. I was surprised and pleased when I received my covers back from Colgate. They are using an unusual bicolor handstamp, probably to time date arrivals.