I've just stumbled upon Prism by Mozilla Labs (Prism)
It's a lovely piece of software which allows you to have a website open as a standalone application (of sorts). It's completely separate from your browser so doesn't interfere with it at all.
It comes as either an installable application or a Firefox add-on.
Take a look at the features list on the website to see what else it does.
Personally, I use it to access my Google Calendar.
Double-click the icon on my desktop and there it is already logged in.
Lovin' it. :D