SURE, YOU want to stay out late, you go to a bar -- any bar, any night, anybody could tell you that. But maybe you'd like a little more to experience than that Michelob Light or Midori Mothbuster or whatever it is you're drinking these days -- some special atmosphere, say. Some like-minded stay-outs to surround you, say. A late-night reputation, say.

Say. What an incredible coincidence. We just happen to have here this semi-representative but duly arbitrary sampling of four in-town clubs where, traditionally, midnight may have come and gone but more people are still coming in than going.

BLUES ALLEY -- Wisconsin and M NW. 337-4141. The midnight shows (every Friday and Saturday nights) by the Alley's big-name jazz headliners are generally looser all around -- meaning a higher Jam Probability Factor on stage and a lower one, elbow-wise, at your table. Plus, of course, Blues Alley is in the center of Late-Date Nirvana, also known as Georgetown. So. Wear comfortable shoes -- preferably $150-a-pair soft Italian calfskin jobs -- and bring a few friends who can block for you when you hit Wisconsin Avenue.

CHARING CROSS -- 3027 Wisconsin Ave. NW. 338-2141. Speaking of Wisconsin Avenue, melting pot of Porsche owners from around the world, here's a place named after a London subway stop that serves Italian food, and the bartender is named Aziz. Whatever. The reason Charing Cross is mentioned here is its nightly happy hour -- and that's nightly as in midnight to 2 a.m. Sunday-Thursday, and 1 to 3 a.m. Friday and Saturday. A good place to go and argue, amid a collegial, big- chill, cheap-drink atmosphere, about the late show you saw at the Biograph or Cerberus theaters up the street.

CHILDE HAROLD -- 1610 20th St. NW. 483-6702. In the middle of the Dupont Circle-Adams Morgan axis -- the best overall area in town for one of those after-midnight walks with our hip urban friends -- the Childe Harold is almost always busy until late (both inside and, while it's still nice, out on the patio). The clientele is a funky amalgam of haves, have-nots and don't-cares -- plus there's your assorted network-TV types, your romance-oriented couples (who gravitate to the little semi-private side room, under the stairs), your memorable jukebox and a very big guy in a sweatsuit who looks just like George Starke, standing next to you at the bar. Wait -- it is George Starke. Could've used him in Georgetown.

9:30 CLUB -- 930 F St. NW. 393-0930. This club -- the place in town to hear live, loud, eclectic and generally out-of- town new music -- has long been popular among the late-at- heart, though it also helps to be young (at heart and otherwise), and maybe also hard of hearing. (Just kidding. I said, JUST KIDDING!) On most weekend nights, there are music sets that start at midnight; other nights, if there isn't live stuff after midnight, there's always some life-threatening video dance fare -- and plenty of people around who just got there, many of them wearing all-purpose black, others wearing stuff not normally available at Hecht's, except maybe in Housewares.