TONIC (3155 Mount Pleasant St. NW; 202-986-7661) is a new neighborhood bar in one of the city's most diverse and eclectic neighborhoods. Of course, it's hard to just open a "neighborhood" bar -- that's a title that must be earned over slow off-nights as well as packed weekends, as locals stop off on their way home or just come by to hang out and socialize. But Tonic is off to a promising start.

The beauty of Tonic is it doesn't try too hard to have a hip, unpretentious vibe -- it just does. Exposed brick walls and dark wood fittings in the low-ceilinged basement space give off a warm glow. Three television screens hang behind the bar, and groups are clustered around most of the tables. Upstairs, the nonsmoking restaurant is sunny and colorful, faux-finished and decorated with vintage posters.

"This is a really cool neighborhood place," says co-owner Jeremy Pollok, who most recently managed a trio of the city's swank hotel bars. "I loved Helix, Topaz and Rouge. I thought those were really great places, but they didn't personally fit me."

"You're not that cool," offers co-owner Eric "Bernie" Bernstrom. "That's what it is."

Bernstrom and Pollok are old friends; they met in 1996 while bartending at Republic Gardens and were reunited a few years ago at Topaz Hotel's stylish bar. Pollok went on to work at Bar Rouge and Helix Lounge, but he and Bernstrom were itching to open their own place. The chance fell into their laps last fall.

Bernstrom has lived in Mount Pleasant for more than 10 years, including a spell on the third floor of this building. So when the owners of the Bella Roma Italian restaurant were looking to sell, Bernstrom and Pollok jumped at the chance. They took over in November, and unveiled new signs, a new menu and a new look earlier this year.

Already, Tonic is the best kind of local tavern, where, when someone walks in, most people turn and look -- not because they're checking him or her out, but because the new arrival might be a friend or neighbor. (Okay, maybe they're checking the person out.) It's the kind of place where, if you're sitting by yourself, the bartenders make conversation, or draw you into conversation with other folks at the bar.

During an Orioles rain delay last week, a bartender handed the satellite remote to customers and asked them to find something else to watch while she whipped up some cocktails. Then she laughed (and didn't complain) when a group of guys stopped on the Ultimate Fighting Championships and spent the next half-hour watching no-holds-barred brawling on the plasma screen. Regulars know that certain shows will always be on -- "The Sopranos," for instance -- although there's no theme party with special drinks. Tonic is just an extension of Mount Pleasant's communal living room.

"Thursday, Friday, Saturday, I don't recognize half the people that come in here," Bernstrom says. "Weekends are great, but Sunday through Thursday, we get a group of people who are . . . definitely your true regulars."

"There's a guy who comes in here, he's gotta be 70 years old," Pollok says. "He comes in every day, has a couple of beers and leaves. Then there's a 21-year-old who does the same thing. It's your typical neighborhood place, and it's neat, because you get to see those people communicate, when in everyday life, they don't, for the most part."

With a happy hour like Tonic's, how could they not wander in? From 4 to 7 Monday through Friday, all beers, burgers and mixed drinks are half-price. Shiner Bock is $2, Guinness is $2.50. Burgers (veggie or regular) are less than $5. The deals are "a way to appreciate the regulars," Pollok says. "They're our bread and butter. Why not have something for them?"

Cocktails are another specialty -- many of the drinks from Topaz have made their way here, including the citrusy Blondie and the cranberry-vodka Catatonic. At $7 each, they're a veritable bargain.

Every time I stop by for a drink, I find myself staying to eat. Choices include well-made pizzas (named after nearby streets), cheesesteaks, bratwurst and pulled-pork sandwiches, as well as the full restaurant menu from upstairs -- rockfish filets, crispy half-chicken and a huge couscous platter. "We're not trying to be fine dining," Bernstrom explains. "We have tater tots with all the sandwiches. It's American comfort food, made from scratch." Families have been flocking in for the children's menu, especially on Wednesdays, when kids eat free with the purchase of an adult entree.

The intimate feeling doesn't just come from the neighborhood clientele -- Tonic really isn't that big. Walk past the bar, and you'll find a few more tables. That's it. Pollok wants to turn a rear storage room into a game room of sorts, with darts, maybe a Golden Tee machine, and a few more seats. "There's nowhere around here to go and play darts," he says, although there's no timetable for the addition.

Not surprisingly, Tonic's jukebox is also worthy of praise. Yes, there are places that have digital systems with thousands of albums available, but smaller, older jukeboxes are really a window into a bar's soul. The selection here is pretty diverse, veering from Hank Williams to the Beatles to Marvin Gaye to Massive Attack to the Pietasters. "[When we got the jukebox,] there were a couple things that weren't in there that you needed to have: it didn't have Bowie, it didn't have Zeppelin," Pollok says. Still, Bernstrom concedes that "the Raven might have us beat" with its selection of classic drinking music. Says Pollok: "Yeah, when I think of jukeboxes, I think of the Raven. We did a little scouting there." (Hence the Johnny Cash, Patsy Cline and Motown CDs at Tonic.)

Mount Pleasant needed a bar like Tonic, but I have to wonder about the effect on the older, more established hangouts like the Raven, Marx Cafe or Dos Gringos. "I don't think we're pulling off the Raven or Marx at all," Pollok says. "I think another restaurant in the neighborhood would help us more than it would hurt us, you know, make Mount Pleasant more of a destination."

Bernstrom thinks there's room for everyone on Mount Pleasant Street. "If you want to go drinking and drink hard for cheap, you go to the Raven. If you want to hear a DJ, go to Marx [Cafe]. If you want to hear Latino music and sit down for some good food, go to Haydee's. If you want a beer and sports fix and American comfort food, come here."

HOT BARBECUE AND BLUES

For nightlife gourmands, some things just naturally go together: Martinis and Sinatra tunes. Beer and polka. Barbecue and blues music.

One of my favorite new places for the last combination is Ellington's on Eighth (424A Eighth St. SE; 202-546-8308), a cozy little cafe and jazz club near the Eastern Market Metro station. Every Thursday night, while duos and trios perform on a tiny stage dominated by a kente-draped piano, customers relax on armchairs that line one wall, sipping coffee or beer and nibbling on heaping plates of soul food.

In the rear of the room, tempting smells waft from Sterno-heated chafing dishes. It's not fancy, but the greens are tangy, the barbecued pork is smoky and well spiced. Sweet barbecued beef, creamy sweet potatoes, hunks of corn bread, gooey macaroni and cheese -- it's delicious "home cooking," and you're welcome to go back for seconds. Just be warned that the staff will urge you to "save room for some chocolate cake" and the buffet closes about 10, an hour before the music stops.

Sisters Marsha and Annette Martin opened Ellington's on Eighth on Mother's Day 1998, and their storefront restaurant and cafe is one of the underrated spots on Capitol Hill. Wednesday through Sunday, Ellington's offers live music, drinks and a gathering place for the neighborhood's diverse population: gay and straight, black and white, old and young. Everyone is welcome; there are annual parties to celebrate Capital Pride, the Super Bowl and Martin Luther King Jr. Day. Children are welcomed with booster seats and games. And when the Martins talk about serving the community, they're not kidding: Ellington's serves as a training ground for homeless men and women seeking jobs in the hospitality industry.

Styled as a "garden cafe" and "champagne lounge," Ellington's almost lives up to the billing. The rear patio, with a high wooden fence and greenery, is a great place to enjoy the warm weather with a cold pint of Tusker beer (from Kenya) or the dark, chocolatey Abita Turbodog (a brown ale from New Orleans). And though it's somewhat pedantic to point out, few of the bottles on the "Champagne menu" are actually from France, but there's not a bad selection, and the house cocktails -- including the spicy Red Sea -- are worth exploring.

While there's no real bad time to go to Ellington's, Friday's Latin-jazz flute trio led by Arch Thompson and the "BBQ and Blues" buffet would be my recommendations, though those seeking harder-edged Delta or Chicago blues won't find them here. (Also, don't be surprised if Thursday's music is punctuated by open-mike poetry; the Martins actively support spoken-word performance.) Far more relaxing is the Sunday brunch, which mixes mimosas and breakfast platters with jazz and gospel tunes after noon.

* The "BBQ and the Blues" buffet costs $10.95 and is served from 6 to 10. Music begins at 8.

Tonic, a new neighborhood bar in Mount Pleasant, is an intimate space with a friendly atmosphere. Great happy-hour deals are "a way to appreciate the regulars," co-owner Jeremy Pollok says. "They're our bread and butter."Cyndi Lopez, who lives near Tonic, cranks up the bar's old jukebox, with its diverse collection of songs by artists such as Hank Williams and Marvin Gaye.