There’s a great chinese restaurant in the financial district called Yank Sing.
Best. Dim Sum. Ever.
• Just walk across the Golden Gate Bridge. That’s really the best way to experience its grandeur and appreciate the view. Dress warmly.
• Everyone except the faint of heart has to ride the cable cars before leaving San Francisco. There are three lines; all originate at Market Street, the main downtown avenue. The most exciting: the Powell-Hyde line, from the corner of Powell and Market, going to Fisherman’s Wharf. Seven days a week from 6:30 am to 12:30 am. (Don’t confuse SF’s cable cars with SF’s trolley cars, which are basically electric buses.)
• Alcatraz Island. The National Park Service offers tours. Don’t miss this.
• Muir Woods National Monument, a stunning redwood forest on the other side of the Golden Gate Bridge.
• The musical revue Beach Blanket Babylon, a SF institution now in its 29th year, but always topical. Wednesday thru Sunday.
• Take one of the Wok Wiz tours through Chinatown, seven days a week.
• The Castro Theatre, San Francisco’s landmark movie palace. Every show is preceded by a live performance on the theater’s earth-rattling pipe organ. Seven days a week.
• Restaurants: Cha Cha Cha, a Caribbean bistro in the Haight-Ashbury district; Kokkari in the Financial District, SF’s best Greek restraurant; Maykadeh Persian restraurant in North Beach. I’m getting hungry just thinking about them.
• SF Weekly has a guide to local events, the music scene, clubs, theater, etc.
Definitely Alcatraz. Amazing place to visit (but I wouldn’t want to live there). 
Also, remember one thing if you’re walking: if they call something a hill, they lie.
Another vote for Alcatraz. If you do it, be sure to book pretty far in advance, or you won’t be able to go.
If you go to the Exploratorium (which I recommend), call ahead and get reservations for the Tactile Dome, as well.
The view is great, and i also really like the WPA murals inside the tower.
My girlfriend grew up in SF, and her mother still lives there, so we get to go there fairly often. While some of the tourist stuff can seem corny, there’s a reason that so many people do it–because it’s fun. Riding a cable car on Powell Street, or going to the Golden Gate bridge, or wandering around Ghirardelli Square, are all worth doing.
I really like the Cable Car Museum. There’s not a whole lot to do there, but it’s great to see all the massive wheels and engines and cables running to keep the cable cars moving up and down those amazing hills. And it’s free.
I was out in SF a couple of weeks ago, and while my girlfriend and her sister and mother went to the Kabuki Baths in Japantown (apparently fantastic; they have men’s days and women’s days) i rented a bike in Golden Gate park and went for a ride. I rode down to the beach, then back up the park, north on 30th Avenue to El Camino Del Mar, then up into Lincoln Park to the Legion of Honor. After that, i rode back down the hill and along Clement Street to 6th before returning to Golden Gate Park and reading a book on the lawn outside the Conservatory of Flowers. That route gives you great views of the ocean, then of the Golden Gate and the bridge, as well as a nice tour of the Clement Street shops and restaurants. It’s pretty hilly in places, but on a nice day it’s lots of fun.
My girlfriend would agree with you, i think. She loves that place. Unfortunately, i haven’t yet had the opportunity to go. But the food in SF is great in general.
And another vote for the Castro here; doesn’t matter if you’re gay or not. Actually, having grown up in Sydney, Australia, i find that San Francisco doesn’t seem any “gayer” (whatever that really means) than my old home town. There’s certainly no reason to think that you have to be gay to have a good time.
A place that no-one has mentioned yet is Fort Point, right under the south end of the Golden Gate Bridge. It’s a National Historic Site, it has a great view of the Bay, and the interior of the Fort has some fascinating historical stuff. I also like the historic ships that are part of the SF Maritime Historic Park.
If you want to see some tourist-type pictures that i took on a previous visit to SF, which include some of the places i’ve mentioned here, you can check out my pBase page.
Good things don’t end in “-ium.”
They end in “-mania,” or “-teria.”
My favorite part of Fisherman’s Wharf is always the sunbathing sea lions. 
Define “dress warmly.” I’m going to San Francisco in the first week of May for a training class, and I really want to squeeze in as much sight-seeing as possible. Do I need a winter coat for something like this, or will a light jacket and sweater combo work?
As for bars, let me recommend Pompei’s Grotto (350 Jefferson, on the Wharf) on Friday or Saturday, tell the bartender Jeff sent you. Hell, I may just meet you there. It’s very Cheers-like, nice, quiet atmosphere, but with some pretty nutty people, and that’s just the employees. Trad’r Sam (25th Ave/Geary) is kind of divey, but it has a nice tiki kitsch to it, and the drinks are fantastic. Gotta have a Scorpion Bowl. It’s crowded as hell Thu/Fri/Sat, though. Can’t smoke in either (it’s illegal to smoke in bars, but there’s plenty of places that allow it).
Check out SBC Park, 3rd/King. Even if you don’t like baseball or can’t get in, there are some beautuful plazas immediately surrounding it, with some great views of the Bay Bridge, the Bay, and SOMA.
If you’re going to walk the Bridge, dress real warm. “Warm California Sun” doesn’t apply to San Francisco. No to mention you’re suspended above a waterway. It’ll probably be cold (~40ish with wind chill) and windy.
Stop by Twin Peaks if its somewhat clear, day or night, for one of the best views of the City. Can be crowded on weekends, though. You can also stop by it’s little brother TankHill, near the NE foot of Twin Peaks.
I’ll second Beach Blanket Babylon, and I’ll also recommend Noises Off, playing near Union Square. Also, in the parking garage beneath Union Square, there is a Half price theater ticket window, where you can get great deals on shows in the area.
Feel free to AIM me (same name) if you want any more info, I’m happy to show off the City. Do a search, if you can, on this. I remember a very similar thread maybe two months ago.
Oh, and San Francisco isn’t big enough to have any five-digit addresses, much less up to 60000. ;D
Addendum: Beach Blanket Babylon is incredible! Check it out if you can.
Yank Sing is no longer in the Financial District. During the dot.com boom, someone bought up their building to build a hotel-- this was maybe 3-4 years ago? Then the whole boom went bust and the hotel has been empty ever since. I work near there-- I was more bummed that the Arby’s also disappeared, but YS is known for GREAT dim sum.
Yank Sing is now around Montgomery Street just south of Market, I think. You can look it up on the web. Also, the place was so darn popular that for the last 3-4 years they have stationed employees under an umbrella at the old location. They will shuttle you to the new location for no charge.
If you’re into circusy kind of things with slightly gay flair, you can’t go better than Teatro Zinzanni
That’s true. It’s now in the Rincon Center, which incorporates aspects of SF’s old, historic post office.
I was in SF last week. My mother and her husband keep a spare apartment in Oakland so I had a free place to stay.
If you plan to do any of the touristy stuff like the Exploratorium, a Bay boat tour, the SF MOMA and the Legion of Honor art museum, you can buy a CityPass at any of the venues. It gets you free admission to all these places plus a 7 day MUNI pass, so you can ride the trolleys, cable cars and buses for free. I’m not sure if you can substitute the Alcatraz tour for the Bay tour - they’re both run by the parks department and they sell the tickets at the same place.
My sister and I also took a couple days to go down to Monterey. It was great - not crowded and very pretty. On the way back we stopped at the Winchester Mystery House and did their tours.
I think my niece was most impressed by the 3-story Old Navy. 
StG
The light jacket and sweater combo should do, maybe add a hat. It will be windy.
Thanks! As you can see from my location, I don’t understand the jacket in summer phenomenon.
But you said in your OP, dated March 19, that you would be going to San Francisco in a week or so, which would be early spring, not summer.
A bay cruise at night. When you round the bend to see the Golden Gate Bridge and the city on a hill, what you see will take your breath away.