05/07/2012 08:50 pm ET Updated Jun 15, 2012

Hugh Hefner: Playboy May Have Left Chicago, But Hef's Little Black Book Stays Behind (PHOTOS)

Although Playboy magazine officially uprooted its Chicago offices to head west for Los Angeles last month, the magazine has left behind several relics, including the little black book that once belonged to its legendary founder Hugh Hefner.

Last Friday, the Chicago History Museum unveiled its new display of Hefner's address book, part of "Unexpected Chicago," a rotating exhibition that changes every two months. The lore of the book, the museum notes, "implies a secret world of go-to contacts -- actual names or pseudonyms -- its user has cultivated and maintained." Such a lore, at least in non-digital form, is rarer today. The book was modified to cover the names and addresses of the people listed inside.

The museum also features a number of Playboy relics as a part of its "Crossroads of America" exhibition.

Of his company's Chicago farewell, Hefner, 86, wrote fondly of the city where he spent his college, Army and early Playboy magazine years, calling it "the most significant representation of true, post-war America."

Today, Hefner lives in Los Angeles and the Streeterville building where his company was formerly headquartered has been subleased by the Chicago's Children's Memorial Hospital to house its foundation, finance and legal departments.

All images appear courtesy of the Chicago History Museum. Click here if you are interested in obtaining a copy of any of the museum's images included in the slideshow. Their call numbers have been included for your reference.