My Lockbox Free is an easy-to-use tool which can help you to hide, lock and (optionally) password-protect almost any folder on your computer.
It only takes a moment to set this up; just point the program at the required folder, and you're done, it'll disappear from Explorer. Only when you use the Unlock button (or choose to protect another folder) with your data return.
Please note, My Lockbox Free is severely restricted, and allows you to hide one folder only (although this may in turn contain any number of subfolders). To remove this restriction and hide as many folders as you need you must upgrade to My Lockbox Pro. The program is priced at $24.95 and you can order at the author's site.
On balance, though, we'd say both Lockbox editions are only really useful against inexperienced users. With the right tools you can easily bypass it and see files within the protected folder, so don't assume the program offers you serious protection.