You didn't hear this from me. Like all good San Franciscans known to drink and prowl the streets, I have been sworn to secrecy on 1) the location of these slides and, 2) exactly how much freakin' fun they truly are. Take yourself, your friends, and an oily pizza box to Douglas and Seward (yes, a schlep uphill near 20th Street) in Castro/Noe and slide the unmoderated, unexpurgated concrete steps at your own risk and to your heart's content. Map here: http://maps.google.com/maps?q=Douglass+St.+%26+Seward+St.%2C+San+Francis...