If you haven't heard of Clint Davis, you surely will soon.  This is because with a mailer marketing strategy like this, he's going to be getting all kinds of work from agencies.  You can read his full blog post as well as see all kinds of behind the scenes photos and detail here (click the link).  In this awesome short video Clint Davis shows what it takes to stand out when sending mailers to agencies, especially when hundreds of mailers hit their desk!