It's kind of a letdown to leave Herb's and suddenly remember you're in a city where the subway shuts down at midnight. That's a whole hour before even Herb's kitchen closes. What is this, Dayton?

No, actually, this is Dupont Circle -- possibly the closest Washington will get to Soho, Chelsea or Columbus Avenue. With more places like Herb's in Washington, though, the distance between the Big Apple and the Big Sleep will seem considerably shorter.

Herb's is not just open late. It's also open, period. The person at the next table -- under the snapshot of Livingston Biddle or the cast portrait of an Arena Stage production -- may be a leather-bound punk, a Lacoste-bound gay or a homebound City Council member. Or it may be Elizabeth Taylor. In any case, act nonchalant.

Herb White says the restaurant he owns, unlike its nonchalant owner, was not made in New York -- but it sure tastes imported. Here, in a town that even has a radio station named Lite, is an oak-and-glass, bistro-style safehouse for the weighty -- artists, poets, dancers, actors, musicians, writers. And also for the weighty-watchers, who are people (much like Herb White) who'd just rather be surrounded by bohemian trend-setters than, say, tax attorneys or congressmen.

White has spent 30 of his 48 years thinking New York but living in Washington (and variously owning or operating the Ontario Theater, the Cafedon in Adams Morgan and Virginia's Wayside Dinner Theater). He's wanted to do this for a long time: to run a "nice place" in which his spiritual kin -- "the artistic community," as it were -- could feel at home. And one where they could spend less than in most comparably "nice" places with consistently good food and consistently efficient, bright people to serve it.

Now, the food (the work of an American- Thai-Latino cooperative in the kitchen, which also handles room service for the Georgetown Hotel upstairs) isn't exactly cheap enough to steal starving-artist regulars from Nardo's Middle-Eastern pizza carryout around the corner, but it's not expensive either -- considering the imagination and generally fresh stuff that goes into it. Lunch main courses run about $4 to $6, slightly more for such daily specials as the Santa Fe -- an open-faced melt of smoked turkey breast, Monterey Jack cheese, jalape?no mayonnaise and avocado. Dinner entrees run $7 to $11.

The clientele, like the neighborhood, is a good part gay; the help is a better part happy. The happiness is traceable to White, whose bartenders, waiters and waitresses are often also dancers, comedians and painters -- and whom he encourages, through his own laid-back example, to be themselves. "I never really wanted to be an adult, and being in the restaurant business makes it easy," he says. "Maybe my employees have less of a problem dealing with another kid."

White took over the Georgetown Hotel's perennially foundering restaurant last year for a relative song; he tries to pass on the savings to the public, particularly the arts- related public. Working artists and selected periphery can get, from White himself, a "guest star" pass that entitles them to happy-hour prices any time of day (55 cents for a National Bohemian draft, 80 cents for other domestic drafts, $1.35 for rail drinks, $1.75 for Bass Ale on tap; non-happy-hour prices are 20 to 50 cents higher).

White also makes his two private rooms available, with free buffet and discount drinks, to various arts-related groups for meetings and parties. His large dining-room roundtable, known semi-seriously as "the Algonquin South," is also pretty popular -- and considerably less pretension-prone than its Manhattan counterpart.

Be aware, however, that if you don't recognize more than two artists, journalists, performers or egomaniacs whose photographs cover the walls of Herb's, you may not feel at hr Streeome here right away. In this case, just smile and nod a lot. When you get home, subscribe to The New Yorker. HERB'S RESTAURANT -- in the Georgetown Hotel, 2121 P St. NW. Kitchen is open 7 a.m. to 1 a.m. seven days; bar is open until 2 a.m. Monday through Thursday, 3 a.m. Friday and Saturday. Call 333-4372.