396288 Facebook Twitter Viral Link

I would like a link on my website to become available to a visitor only once they have either published my site to their Facebook wall or they have posted a tweet about my site on Twitter. I am looking for the coder to come up with suggestions as to how this can be achieved, but the end solution must meet the requirements set out below. 1) The intent is to provide a link to free content on a webpage, but allow visitors access only once they have promoted my site by either publishing to their wall an advert (containing hyperlink) or posted to their Twitter page an advert (containing hyperlink). 2) Third party software is allowed and encouraged. For example if the coder can implement this using ShareThis or AddThis etc, that would be ideal. 3) The process must be instant. In other words, the user must be directed to the protected webpage (or have the link activated) immediately after posting to their wall or Twitter page. 4) If the coder intends to produce their own GUI (i.e. not use graphics from a third party) it must be clean and attractive. The provider must submit to me for approval any images or graphics they intend to use. 5) The provider must describe to me the user experience they intend to provide in their bid. This needn't reveal how they will achieve the project but it should give me a good idea of what the user will experience, and allow me to determine if the proposal is acceptable to me. 6) The provider must implement the functionality on my website. My website it coded in HTML and it should be assumed I have no technical knowledge. 7) I have attached a mock-up of how this function could work in practice. However this is just an idea and I will entertain all proposals for achieving my intention. 8) I will retain all ownership of the work provided by the provider. Please contact me if you require anything clarifying. Thank you.