While my method isn't as secure as your most likely is, I prefer a simpler algorithm based upon the site name. I can perform my algorithm in my head and enter a password quickly and without having to refer to a terminal or another program.
Btw, do you ever worry that your command history might be accessed to discover your passwords?
I use an app I wrote to do the sha1 so the sentence is not hanging around in bash history, but I do rely on the cmd prompt at times on computers at my house. Here's a screeshot of the app: http://i.imgur.com/tz255.png
Btw, do you ever worry that your command history might be accessed to discover your passwords?