Posters are one of the most cost effective forms of advertising on the market. Posters allow you to spread your message to a wide audience far cheaper than radio, print or television advertising in a simple, easy and affordable way. Posters are credible. Posters provide a logical and cost-effective way of communicating to a ... Yes, they still come in the standard, 24- by 36-inch size popular with rock groups. ... but a poster in color will probably make your message stand out best.