In honor of the release of its new cologne named Pure, Hugo Boss bought out entire subway trains in New York City. The one pictured above is a subway car at a stop in Times Square and the campaign is clearly meant to get a lot of impact and awareness of the new product.
The ads are meant to resemble a wall of water, and with the subway cars engulfed in them, it feels as if you're riding in a tunnel of water. Jet Blue has done similar purchasing patterns - buying all the ad space in whole subway cars - but has never actually decorated the whole subway car for the purpose of advertising, like Hugo Boss did in this case.
The campaign is effective because of the high-traffic lines on which this particular subway car runs, as well as because of its obvious presence in the subway car. People riding on the subway are simply in transit with the advertising message directly in their faces.
Use this as inspiration for your next promotional campaign. Promotional posters and promotional stickers, when used in the correct location and manner, can be extremely effective at capturing and maintaing the attention of the target audience, and driving awareness as well as sales.