I occasionally see people with Rapidshare accounts post a password along with their links. How do you use these things? Don't you need a Login/User Name as well as a password?
I am unsure if you are referring to rapidshare folders or just files which are sometimes password protected by the uploader?
Some people password protect their files. The password given is needed to open that file when it has been downloaded to your computer only.
Password protecting files helps keep them on filehosters servers for longer as many filehosters such as rapidshare don't actually allow porn to be uploaded and will usually remove the files when they find out.
You can download from rapidshare without an account but they have a daily download limit for unregistered users.