Last year it looked like the Cliff Dwellers Club was a goner. Housed at the top of the Borg-Warner building, with a multimillion-dollar view overlooking Millennium Park, the arts club, founded in 1907, was facing eviction. Not only did it survive, it's in the midst of a renovation designed by Skidmore, Owings & Merrill, which seems appropriate given its ties to Chicago architecture. Frank Lloyd Wright was a charter member, Louis Sullivan took refuge there, and now the Chicago Architecture Foundation is offering tours of the place. The tours, however, aren't likely to include drinks on the terrace or a nude dance performance by an artist in residence. And those are the Cliff Dwellers' raison d'etre—the club was founded to provide "a place where people seriously interested in the arts . . . could come together in a congenial and friendly way." Over lunch at the members' table, say. At a meeting of the Society of Midland Authors or a Bloomsday reading of Joyce's Ulysses. True, it's all for members (or by invitation) only. But, says a friend who witnessed the nude dancer doing his thing, the Cliff Dwellers are "very chill."