Playboy Press has published Hardcovers that mimicked Playboy Newstand Specials as well as non-related topics and Lifestyle topics. Collectors have cherished some hard to find Hardcover Editions for years. In fact, there is even some question about whether or not some editions actually exist. Some later editions (after 1980) are actually more valuable because of the demise of the Book Club, and thus, these issues were less widely distributed. As best we can tell, there are Hardcover Editions for almost all of the softcover editions that were published. (NSS).
There are known "Hardcover Compilations" of monthly magazines, as well as VIP magazine that are somewhat scarce, as they were issued to Playboy executives (as I understand it). I have seen some, and they are basically bound matter in a hardcover binding. As we understand it, some of the harder to find Hardcover Editions are the "Best From Playboy" series, as well as the Girls of Playboy #4 and #5. Vargas Girls and Little Annie Fanny are also scarce.
As a side note, Waldorf Publishing Company did many of the earlier Hardcover Editions.