Best Crazy S.F. Place to Take Out-of-Towners

Dr. August Coppola (Francis' brother and Nicolas Cage's dad) designed this touchy-feely 1971 oddity -- a one-way maze inside a geodesic dome that you must feel your way through, in complete darkness. Coppola built the attraction so that one must climb, crawl, slide, and fall to get to the end, encountering surprising and delightful textures and objects along the way. The Tactile Dome is located inside the Exploratorium, and you must make reservations and pay a bit extra to get into it. It's fun for kids, and you can rent the entire thing out (think birthday parties!) if you have a minimum of 15 people (it costs $14 a head, which includes the price of entry into the museum). Rumor has it that with advance notification, you can even go through in your bathing suit, for maximum tactile stimulation -- corporate team-building anyone? The Tactile Dome, which takes about 10 minutes to traverse, was once a favorite something-to-do-on-acid experience of hippies, who took much longer. Lucky for them, if you get claustrophobic and start to freak out, the attendant will turn on the light and let you out.