Watch this video. It's a hilarious interview with a prisoner who talks about how he "self-learned his self" through doing drugs. I have no idea if this is real or not, but can you imagine how successful a viral marketing campaign would be that had videos that were this funny?

Here's the lesson: many people are online looking for entertainment, and if you can create entertainment and weave a marketing message into it, you'll have a successful viral marketing campaign on your hands. It's a great way to stand out in a crowded marketplace.