I had used Scribd.com and in order to download anything they asked to upload and share something or pay for the download --- Now I feel this is a good business model especially when you are a startup and when you don't have any data on your website.
I am thinking of starting something similar to this business model - where a person needs to give something similar in order to get something from my website (lets say my website is a database of PowerPoint presentations and if someone wants to download any ppt he needs to upload some PowerPoint which he has). This way I think I can develop a good database because everyone who wants something is also giving something.
Now my question:
It's somewhat like a sharing business. For example there's a website (I forget the name) where you send a book you're done with to someone else, and you get credits for others to send you books you want. This can vary from pure sharing where you just enable the interactions and don't get any revenues, to a percentage-fee model where you get something on every transaction so people don't get as much as they put in, to an information exchange community where you provide most of the value but others can contribute something instead of buying it (sort of like having a conference and letting speakers in for free).
Stack exchange itself is an example of this. It may be relevant since people need to contribute something of value and not just answer 1000 questions before they can get additional privileges etc. You definitely need to be careful because if you ask people to submit an email address or upload a file to get something they won't necessarily submit their email address or upload a useful file.
The Sharing concept is for good will it is on the concept of "sharing is caring" I don't think there isn't any revenue model in it. I always visits a forum for Oracle Users, the forum name is club oracle, where a user needs to upload a document to download a file.
For building that website first he concentrates more on traffic and then a loyal user base.
If you want to implement this model first be acquinted with two or three subject matter experts and have a partnership with them, make those guys upload quality presentations on your website after that source traffic to your website. make sure that visitors to your website won't able to download more than five files per day and the download facility should start after verifying the download.
You Can make this business profitable after getting good user base and making your website a market place for the product whereby a user can sell his work with a commision to