Had a quick look on Google and all I can find is expensive software. There must be some way of adding password protection to a folder?

Reason I ask is that most of my private and personal data is now on a small external hard drive. If I lose that and someone finds it all they'd have to do is plug the usb cable in and they'd get all my data!

There is an app called Folder Password Expert that, after reading this article, seems to do what you want.

However the cynic in me knows that anything working at the file system level can easily be defeated by someone with a little know how. For me I would use some form of encryption. All depends on how sensitive the documents/images are.

What I showed my pal a wee while ago was how to put a password on a RAR file

Once you set a password on them they are pretty much bullet proof, in my experience anyway

It was to hide his porn fi his current burd

I hope he named it something suitable to throw off the scent, something like 'Discussions on Plata and the Homeric Influence on Western Literature'. I find that usually works.

I use an encryption program called Instant Lock that password protects, encrypts and removes encrypted files and folders from sight - even if you choose to view hidden files.

There's a free trial version of it here

When you install it, you will be prompted for a password, this is whatever you choose it to be - this will be the password you use to encrypt and un-encrypt your files and folders.