After you build some content in an application like Flash that you think other people would find cool, you can make it "portable" with Clearspring. Clearspring has a bunch of tools that you can add to a widget (or a piece of portable web content) to make it easy to post on your MySpace, FaceBook, or blog page (among many others). Basically, this sets you up to create your own viral marketing campaign. You can also log in to see real time statistics on your widget (like how many people posted it on their social networking page, etc). Very cool. And free.