I'd like to offer my product via download when clients purchase a license. Is this possible? Can you do this if it's a video file? Is there any way to embedd a QT file that will require you to plug in a 1-time license in order for it to play?
You may be interested in Kagi. They provide a service that allows you to sell a downloadable product.
You cannot embed a 1-time request for a serial number inside a movie file. Unless you essentially duplicated a DRM scheme like Apple uses with iTunes, it is virtually impossible to protect a video file unless I'm missing something.
You could also make it harder for someone to pirate your video, by embedding it into a web page with Flash or something else that is less accessible outside of the browser (although it's not hard to convert FLVs to another format).
I'd like to offer my product via download when clients purchase a license. Is this possible? Can you do this if it's a video file? Is there any way to embedd a QT file that will require you to plug in a 1-time license in order for it to play?
You can host content on iTunes. It is kind of like "vanity publishing" in that you have to pay Apple and will only make money if the sale of your product covers Apples fees. But the fees are reasonable.