Baltimore Maryland, with its revitalized Inner Harbor and old school art deco high rises, is aptly named "Charm City." It is appropriate, then, that one of the most charming of EVs is now seen crossing town to the delight of tourists and locals. The GEM neighborhood electric vehicle (NEV), with its open doors and pug nose, is arguably the most cheerful car on the road, and it is not uncommon to see people turn and smile when one zips past.

Taking advantage of the unique attributes and charm of the GEM, a Baltimore entrepreneur thinks he has the ultimate application-mobile advertising.

Armed with a patent-pending design, Luis MacDonald created Clean Cities Mobile Advertising (CCMA). The result is a "low speed electric mobile advertising system," whereby utility bed GEM vehicles are outfitted with illuminated billboards. While mobile advertising is not new-large diesel trucks with enormous billboards routinely chug through urban centers-MacDonald feels his creation can fill an important niche in the market.

"They are small, they are friendly, they are cute, and they can weave their way through crowds," he says. "More importantly, they are not intimidating. The driver can stop to chat or hand out materials. This is a huge advantage over the large trucks."

The advertising industry is highly competitive, yet lucrative for those who do well. Outdoor advertising-representing everything from signs on city benches to kiosks, and from traditional highway billboards to blimp airships-is a growing segment of the industry, accounting for $5.5 billion in 2003, according to the Outdoor Advertising Association of America.

Of the many options available in outdoor advertising, mobile advertising is quickly becoming one of the rising stars. Using CPM (costs per thousand "impressions") as a measurement benchmark, mobile advertising rates as low as $1.50, compared to radio ($4.95), network TV ($8.90), or newspapers ($19.50).

As a new medium, however, mobile advertising is a tough niche to analyze. How does one track the effectiveness of a moving target? Pedestrians may see an ad on the back of a truck as it passes by, but can they really identify the message within the chaos of crowded intersections and the general hubbub of city life?

"A person's ability to recall an Outdoor exposure is a function of the strength of the Outdoor ad itself and its relevance to the person being surveyed" says Erwin Ephron, partner of media consulting firm, Ephron, Papazian & Ephron, Inc. This is where Clean Cities feels the GEM cars have a distinct advantage.

These are not just modes of advertising, MacDonald explains. Anyone can put a sign on the back of a truck and drive around the block, and to a consumer, they see… a sign on the back of a truck. There is no emotional appeal or sense of community. Using electric cars, on the other hand, creates a message within the message. People see the car first, and recognize it as a clean, environmentally friendly vehicle. Then they notice the billboard. The emotional appeal of the two together creates a powerful impression.

This system does create its own restrictions. "The GEM is a community friendly vehicle," says MacDonald. "That is why we are very strict about the kinds of advertising we will allow on the billboard. No cigarettes. No alcohol. Nothing risqué. Basically nothing that you wouldn't want your kids seeing."

The fact that his cars are non polluting is not lost on MacDonald, who has spent the last 12 years leasing alternative-fueled vehicles to government fleet operators. He notes that urban pollution disproportionately affects minorities and low income neighborhoods, and believes that electric cars are an important part of the solution. The name Clean Cities is more than just the name of the company-it is the philosophy and the mission.

The company is gaining momentum, but it has not been an easy ride so far. Without seeing the GEMs, many have difficulty envisioning what they look like or how effective they can be in a practical sense. Some can't imagine how something resembling a golf cart can be taken seriously, and others immediately think of Shriners driving in silly miniature cars weaving in and out of parade routes. There is nothing else like the GEMs on the road, so the sales people at Clean Cities have had difficulty explaining exactly what they are. What works best, they discovered, is to simply get more of them out on the road.

For greater visibility, Clean Cities has entered into demonstration agreements with various high-profile corporate citizens, including a City of Baltimore contract signed by Mayor O'Malley that allowed for the demonstration of Clean Cities low-speed vehicles with the City Government Police Department and Public Works operation at the Baltimore Inner Harbor, a venue visited by thousands of tourists on a daily basis. Additionally, Clean Cities has showcased its GEM fleet at highly attended, major events held at Camden Yards, Ravens Stadium, the Convention Center, as well as, indoors at the 1st Mariner Arena. As a result, Clean Cities has been featured on local television, radio and newspapers to further introduce the new classification of federally-approved, street legal vehicles onto the radar-screen for the citizens of Maryland.

In September Clean Cities sponsored a voter registration drive, offering a vehicle with a "Register and Vote" billboard to volunteer registrars. Volunteers drove the vehicle around town, stopping frequently, and collected large numbers of new registrants. At one event, the vehicle was able to squeeze into the heart of the crowd at the Baltimore Fell's Point Festival, and was immediately mobbed. In less than an hour, the volunteers were out of forms. For the next hour parents took pictures of their children behind the wheel of the GEM while the volunteers answered questions ("How fast does it go? How much does it cost?") that most onlookers wanted to know.

Although it is still too early to know how successful Clean Cities Mobile Advertising will be, Baltimore is clearly charmed.

Baltimore Councilwoman Mary Pat Clark in the "Voter Express."

Clean Cities President Luis MacDonald with the "Voter Express" in York, PA.