If you’re anything like me, you’ll have millions of logins for millions of different websites: gmail, bloglines, your blog, technorati…..the list goes on and on…

You’re probably also a bit like me in that you have roughly the same username and password combination for all of these. It’s a bad move, but we all sacrifice security over convenience when it comes to the web.

I’ve been thinking about this recently, probably because I’ve been singing up to a load of new services with roughly the same details.

What if there was an easy way to vary the credentials each time, but still make them easy to remember?

Start With A ‘Base’ Password

Let’s think about varying the password by website. Start with a standard password. Pick a nonsense word (I use a word my daughter invented) and scramble it a little by replacing random letters with numbers. OK, so you’ve got a password like ‘b0bble5′, haven’t you?

Remember this password. It’s going to form the base of all your future passwords. How? Read on.

Varying The Password

Right, so we’ve got our base password. All you need now is a system to vary it per website. For each website you subscribe to, choose the first three letters of the domain name and add those to the front or back of the base password. For a website like Bloglines, your password would be ‘b0bble5blo’. For del.icio.us, it would be ‘b0bble5del’, and so on.

The benefit is that you only need to remember the base password and your own ’scheme’ for varying it. As long as you remember the base password, the website address itself will provide the password hint! And you score a unique password for every subscription!

The Password Scheme

Personalize your system. You might decide to add your ‘modifier’ to the front of the base password instead of the back. You might choose to take more (or less) letters from the domain name, or maybe take a part off the .com, .net or whatever it ends in.

I’ve actually started retro-changing my passwords to comply with this, although to a scheme of my own choosing.

I know this sounds convoluted, but once you settle on a method for creating your passwords, creating and remembering them gets much easier. It’s certainly worth it not to be using exactly the same username and password each time.

Update: Apparently I’m not the first to use this technique (damn), which is otherwise known as password hashing.