Being that eGO is a trademarked name - I can only assume that the way the donation system is set up we might be a legal non profit organization (correct me if i am wrong) and thus, I feel obligated to mention that there should be no promoting of ileagal activities here. Now, this might actually all be wrong, however, its always safe to keep that stuff to yourself.
I am not sure myself of a program to easily check for duplicate files and I suspect that it would be in either less demand as one might think or extremely difficult to write. How many folders do you have with the same name? Have you ever looked at your files with "show hidden files and folders" on? if so, you might realise that everyfolder has a 'thumbs' file and then there is the 'recycler' folder -eesh. Plus, not every file with the same name is the same - or could be different sizes / versions. I'm not saying it is impossible Just admiring whoever managed to do it. Most of the time this is the reaosn to implement your own organization system.