Once upon a time San Francisco was the most pleasure-loving city on Earth; nowadays it's hard to find a restaurant open after 10 p.m., let alone midnight. Nevertheless, a handful of restaurateurs out there are willing to cater to us night owls -- at least until 1 a.m. Among them:

Brazen Head

3166 Buchanan (at Greenwich),

921-7600

The ideally clubby, comfortable, off-the-beaten-track hideaway (its entrance is both dark and nondescript), the Brazen Head serves hearty American food until 1 a.m. -- crab cakes, oysters on the half shell, pan-fried trout, pork chops and applesauce, and a marvelous brandy-flamed pepper steak. Full bar; no checks, credit cards, or reservations accepted.

Taqueria Can-Cun

3211 Mission (at Valencia), 550-1414; and 2288 Mission (at 19th Street), 252-9560

When the desire for a post-witching hour burrito hits you in the breadbasket, these rollicking Mission District taquerias will set you up. Can-Cun's tortillas are lightly grilled before they're stuffed to bursting with veggies, chicken, carne asada, or (what the hell) tongue, brains, or cabeza; fresh avocado adds a silky touch. Tortas and tacos, too, as well as an excellent cantaloupe agua fresca. Bright, fun, colorful atmo, complete with jukebox.

Globe

290 Pacific (at Battery), 391-4132

This tiny, casually hip, late-night standby offers up a menu of satisfying, rustic, Italian-accented dishes: hearty pastas, abundant salads, fire-roasted lamb, T-bone steak for two, apple tart with caramel sauce. The fresh flowers, exposed brick, and subtle lighting give the place an intimate bistro ambience ideal for late-hour quietude. Open until 1 a.m.

Yuet Lee

1300 Stockton (at Broadway), 982-6020

Incredible seafood is served in bare-bones, harshly lit, lime-green surroundings until 3 in the morning: What a concept! Favorite dishes include the deep-fried squid with green peppers, the sautéed clams with black bean sauce, the clay-pot crab with silver noodles, and the crunchy, terrific salt-and-pepper prawns. There are several vegetarian dishes as well. Cash only.

It's Tops Coffee Shop

1801 Market (at McCoppin), 431-6395

Nighthawks will feel right at home at this Edward Hopper-esque diner, complete with jukebox, counter seating, all-pro waitresses, and ample servings. Classics like pancakes, burgers, tuna melts, biscuits and gravy, hot fudge sundaes, and apple pie are joined on the menu by banana- peanut butter hot cakes, waffles ribboned with bacon, and caramel milkshakes. Run by the same family since it opened in 1952, It's Tops serves its hangover-preventive fare until 3 a.m.