Big up to the folks at Channel 4 and their Embarassing Bodies series. As part of the series, they encouraged viewers to text in to get a link to download a video showing them how to check their bits to spot things they should be going to the doctor about. This is supported by a very comprehensive website. All the content is free to view but standard network rates apply.
Anyway, they've had very impressive results and you can read all about it over on Alfie's blog.