Why?

Using the same password for multiple accounts is very unsafe. If one of those sites gets compromised it will affect all your accounts, possibly even leading to identity theft.

The idea behind this site it that you memorise just one, reasonably long, secure master password and use it to generate a set of non-dictionary complex passwords. This password generator works using JavaScript, entirely within the page and no data is ever passed back to my server.

The code is in GitHub.