This has nothing to do with hardware, but:
Go to My AIM, highlight Edit Options, and click on Edit Preferences...
Click on File Sharing (towards the bottom).
A somewhat "secure" way to do this is to put your friends that you want to have access to your files in a separate group. That way you can give file access rights to that specific group.
Choose the folder you want to share (any sub-directories are also shared). Choose your C: drive (or equivalent) to share everything.
Another way to do it is to make people on your buddy list "Display approve dialog", where you get a dialog box when your friend hits that "get file" button, or you can change it to "allow", and it will automatically allow everyone on your buddy list to access your files (not exactly the best idea in the world)
Click OK to save your settings.