Simple mod request - "Add to cart" extra functionality


Let me know if anybody can program for me a simple code to add an extra functionality to the Add to cart button. Please send me a PM with price quote for the following customization:

I wish that the “Add to cart” button to have an additional function that can be defined in admin back-end. Beside the standard add to cart function i wish i can add a custom link or a custom script to be executed when that button is clicked. I wish it to behave in a similar way affiliate links/banners work. Each product added in admin back-end should have a new tab for how the Add to cart button should function. There should be 3 options: 1. normal (default function) 2. redirect to a link that can be entered by the administrator ; 3. execute a script (similar to the script associated with affiliates banners) that can also be entered in admin area.