Fun around town, for $10 or less: Medicine and Rats: Authors William Frankl and Harris Cohen read from their respective works The Merger and Rat Tales and Other Stories (the latter set in West Philly) at Robin’s Bookstore (108 S 13th), 6PM. Free Folky: The Fairmount Park Commission sponsors a folk dancing session with instruction (no experience or partners needed) every Tuesday on the Art Museum Steps (26th and the Parkway), 8-10:30PM. $3 White Rabbits:......