San Francisco is a city of transplants — many knowing little about the city's history other than the Gold Rush and the hippies — who quickly morph into snobs who won't be caught dead on a walking tour with fanny-pack­-toting tourists. Fortunately, now there's a way to learn about the city's colorful past without leaving your seat: Sparkletack, the lively and unpretentious podcast of San Francisco armchair historian Richard Miller (who now lives in Portland). He writes and narrates a new show each week on little-known tidbits of local history, such as crooner Johnny Mathis' athletic career at San Francisco State, Emperor Norton's eccentric exploits, and the alleged origination of fortune cookies in Chinatown. You can listen to the broadcasts, ranging from 10 minutes to an hour and complete with sound effects and music, directly on the Web site or via iTunes — all for free.