"San Francisco is a mad city, inhabited for the most part by perfectly insane people whose women are of remarkable beauty." -Rudyard Kipling
SFGenealogy.com is a site created "...to provide FREE Internet access to genealogical and historical information for San Francisco and San Mateo Counties, and the State of California." The web site provides great information about the history of different neighborhoods, dating back as far as the site's owners can find data.
For example, here is one entry about the long-since-defunct Lone Mountain Cemetery (where USF is now located):
Dates of Existence: May 1854 to 1862
Location: between 162 and 170 square acres
Number interred: 7,000 (1862)
Moved to: see individual cemeteries
Notes: this cemetery was divided into the Calvary, Odd Fellow's and Laurel Hill cemeteries
The site also has rosters of graduates from a number of San Francisco high schools dating back into the 1930s. I noted that most of these rosters were donated by Judy Cerruti, Dianne Wentworth, and Dale Isaacson.
The site also contains research guides, maps, histories of many neighborhoods, old photographs, and much more.
Pamela Storm Wolfskill and Ron Filion have created an excellent resource that will be of interest to anyone with San Francisco ancestry. You can find this online gem at http://www.sfgenealogy.com.