The trend toward atypical 24-hour businesses--ones that offer more than greasy food--made headlines last year when Apple opened a 24-hour computer store in the middle of Manhattan. But Apple isn't the only business catering to late-night consumers. Entrepreneurs across the country have been successfully applying the 24-hour business model to everything from computer repairs to dog grooming.

Tia Grimm, owner of 24 Hour Computer Doc in Tucson, Arizona, used the 24-hour business model when starting in 2000 to get an edge in the competitive computer repair business. But not in the way you might think. "I thought of having a 24-hour business first just because I thought it would come first in the phonebook," says Grimm, "but that didn't happen because they actually spelled it out instead."

Her late-night hours, however, have ended up attracting more customers. "Most computer places close at 5, so I get all the people that are too busy before that," she says. "In this industry, there's a lot of competition so you have to offer something special to stand out."

Although the customers that drop in later at night tend to be a little odd sometimes--like the guy who came in reeking of marijuana at midnight with a litter box and a laptop with chunks of cat fur stuck in it--Grimm says her popular business has helped her support her three children. "It's a little tough sometimes when you work a 24-hour business and have kids; sometimes it's hard to put things down," she says. "But I make my own schedule, so it's flexible when it has to be."

Owner and creator of LA Dogworks in Hollywood, Andrew Rosenthal, says he also works hard caring for his Italian greyhounds that he loves just as much as parents love their children. He was inspired to start the 24-hour business that cleans, trains, massages and photographs dogs when he and several friends couldn't find an overnight daycare good enough for their dogs. According to Rosenthal, having staff present 24 hours is the only truly caring way to run a doggie daycare.

"You just have to be dedicated because [running a 24-hour business] is definitely about going the extra mile," he says. "I always have to be on call, but I also want to be on call. It adds a lot more work, but it's the difference between us and everywhere else."

The only serious hurdle Grimm and Rosenthal say they consistently face is retaining a reliable set of staff members willing to work at all hours.

But Verl Lowry, who helped turn Seattle's 50-year-old Sunset Bowl into a "hugely successful" 24-hour bowling alley 15 years ago, has definitely learned how to delegate tasks to employees that have stuck around. Five employees have worked there at least 30 years, and several others have been on the payroll for almost as long. Being fair to employees and allowing them to have fun is even more important in a business with late hours, says Lowry, who has been Sunset Bowl's general manager for 30 years and convinced the owner to stay open all night.

He also suggests thinking of running a 24-hour business as operating two different businesses. Lowry runs the show during the day when kids' parties and bowling leagues typically fill the lanes. At night, another manager that's been working the graveyard shift for years handles the bowling alley's operations as adults leaving clubs or just looking for some fun after a late shift at work fill the place.

Lowry wasn't initially worried about whether the 24-hour concept would succeed. "Our bowling alley is located in Seattle's Ballard District where there are a lot of clubs nearby, and everyone had to drive by Sunset Bowl to get to them," he says. "There are also 24-hour bars and a Denny's, so it didn't make sense to kick people out at 1 a.m., like I always was doing on that shift."

Lowry was also familiar with the area's demographic, which consisted of many people that got off work late at night or early in the morning. A retired IRS employee that pays a flat fee every year to bowl a couple times a week from about 4 a.m. to 9 a.m. is just one of the off-beat regulars that Sunset Bowl caters to.

Time Change
If you're considering keeping your business open around the clock, keep the following tips in mind:

Consider the workforce surrounding your business. What hours do the people in your area typically work? Has a huge new business opened nearby? Has one just shut down? Employment trends in the area affect the frequency with which people visit your business in the wee hours of the night.

Think of running a 24-hour business as running two businesses. The operations and type of customers that come in during the day can be completely different from those that come in at night, so think of each half of the day as its own business.

Ask yourself whether the surrounding business community will aid your 24-hour business. Even though it helps, a business doesn't have to be surrounded by a community of night owls. If you live in an area where people don't have time for personal matters until after 5, late hours may work for you.