A great outdoor marketing technique is "clean graffiti". Really effective and a great cheap way to get your message accross. This idea is flexible and can be adapted in a number of ways. Hope this is of use......
I spoke to a cupcake company that enjoyed a lot of success (e.g. orders for catering at meetings) when they launched their business by giving out samples from office to office.
Another way of effective marketing is bumper sticker printing. you can place them everywhere easily even on street poles, walls and it is mostly observed that the people place on their cars to demonstrate message or any political slogan. The reason of its popularity is that they can easily be noticed and provides quick and effective outcome to the consumer.