If you think the only difference between most apartment units is the welcome mat, take a closer look at the listings. Many cities have distinctive options available. But some places around the world really stand out and show what multifamily living can offer when developers and designers use their imaginations. From landmark buildings repurposed as residences to a housing complex with undulating floors, here is a sampling of apartments worldwide with history and character to spare.

Smith Tower, Seattle

Seattle's Smith Tower, originally built for a typewriter tycoon when those machines were high-tech, was the tallest U.S. building west of Ohio when it was constructed in 1914.
At the top of the structure, above even the observation deck, is a single apartment. That residence, in the terra cotta-clad tower's pyramid-shaped cap, became grander in 1999 upon completion of a $28 million renovation and rewiring of the building. The project's main purpose was to add modern amenities such as air conditioning and a fiber-optic telecommunications system. But removing a 10,000-gallon cast-iron water tank in the tower's crown allowed for the conversion of a small caretaker's apartment, the office building's only residence, into a multistory penthouse apartment.

Container City, London

 The idea of creative reuse goes an extra step at Container City, a complex of artist studios and residences built mainly of steel shipping containers. The first phase of the project in the Docklands area of London, Container City I, was assembled in just five months in 2001. The result was a brightly colored, three-story structure, with balconies, porthole windows and 12 live-work studios for artists. Soon, a fourth floor was added, yielding three more apartment/studios. The company behind the project, Urban Space Management, expanded it again when it built Container City II in 2002. This added 22 artist work spaces, as well as interconnecting walkways and an elevator.

Armory Arts Village, Jackson, Mich.

 Years ago, nobody wanted to live here. This 19-acre complex was built as the Jackson State Prison in the 1880s, and a 25-foot stone wall, complete with turrets, still surrounds it. But the guards are long gone. The facility, an armory in the 1930s, has been converted into affordable apartments and work spaces for people with limited incomes, many of whom are artists, musicians, designers and other creative types. Armory Arts Village's first phase, completed in 2008, turned three prison buildings into 62 apartments, with additional work spaces and galleries. Plans for the next phase include adding 49 residences for seniors, as well as a community activity center, a gallery in which artists can display and sell their work, and other amenities.

Packard Motor Car Building, Philadelphia

 Designed in 1910, this eight-story building originally housed a showroom and assembly plant for Packard Motor Car Co. Vehicles would be put together as they descended, floor by floor, from the top of the building to the ground floor. Today, the only cars housed here are in the basement garage.
Philadelphia's Broad Street is no longer known as Automobile Row. Although the Packard Motor Car Building retains its dramatic exterior, with large walls of windows and hand-carved cornices, the interior space has been converted into studio, one-bedroom and two-bedroom apartments.

Bass Lofts, Atlanta

Who says high school has to end when you graduate? The former Bass High School in Atlanta's Little Five Points neighborhood has been turned into loft apartments with traces of the structures’ original function. The main-floor hallway still has lockers, for example, and some lofts have blackboards or original doors with transom windows. Bass High School, built in the 1920s and listed on the National Register of Historic Places, was converted into apartments in 1998. A classroom building has 85 units, and the former gymnasium has 18. A third building brings the number of rental units to 133.

The Police Building, New York

 This Beaux-Arts building, complete with a copper dome and massive stone lions guarding its entrance, opened in 1909 as the city's police headquarters. The New York Police Department moved out in the early 1970s, and the 180,000-square-foot structure was vacant for more than a decade. A plan to turn the landmark building into a hotel never materialized because of financing issues. But in the late 1980s, Ehrenkrantz Eckstut & Kuhn Architects converted the building into a 55-unit luxury-apartment co-op.
The success of the transformation helped kick off the trend of turning landmark historic properties into apartment buildings. It also means that you'll need more than a police officer's salary to move into The Police Building, where a four-bedroom apartment was recently listed for more than $16 million.

Ladder 3 Lofts, Lynn, Mass.

Big-city neighborhoods are not the only places where old workplaces have become upscale housing. The trend is also evident in smaller industrial cities such as Lynn, Mass., just north of Boston, where a 19th century firehouse is now a 15-unit apartment building called the Ladder 3 Lofts. Development firm Resource Capital Group converted the former Franklin Firehouse, which housed the Lynn Fire Department's Ladder 3 Company, to luxury apartments in 2006. Previously, the firm converted two other Lynn buildings into condominiums, and their names reflect their workaday origins: the Boston Machine Lofts and the Sloan Machinery Lofts.

Hundertwasserhaus, Vienna

Designed by Austrian painter and architect Friedensreich Hundertwasser, the Hundertwasserhaus apartment complex has become a Vienna tourist attraction, even though the 52 residences themselves are closed to visitors. But there's plenty to see on the outside of this fanciful building, which was completed in 1984.
The structure's fa├žade features bright swaths of blue, red, yellow and white, with lines of ceramic tiles marking the boundaries of separate apartment units. The building has two towers topped with onion-shaped domes, and trees and grass grow on the soil-covered roof. Other plants grow from balconies, and the building has undulating floors and windows of irregular sizes and shapes. Statues and colorful pillars add to the decor.

Metro 417, Los Angeles

 Before Los Angeles had its famous freeways, it had the Pacific Electric Railway mass-transit system. The system's hub, the Subway Terminal Building, was built in 1925 in Renaissance Revival style, with architectural details inspired by 15th-century Florentine palaces. The office building housed a Red Car subway station on its lower two floors until 1955. Los Angeles got a new subway system in 1990, and in 2005, the Subway Terminal Building was reborn as Metro 417, a "boutique-style" residence with 277 apartments.

Watertower of Living, Soest, Netherlands

Dutch architecture firm Zecc Architecten BV won raves in 2004 for its conversion of this industrial-looking steel-and-concrete water tower into a dramatic, modern-looking apartment home. The architectural firm has also turned a chapel and a warehouse into residences in its hometown of Utrecht, Netherlands.
The Watertower of Living, converted from a structure built in 1931, stacks eight circular rooms linked with a spiral staircase. It also has a rooftop sauna.