For a long time now, I've used the Ctrl+Enter shortcut in Internet Explorer (and many other browsers I've used) to surround a website name with www. and .com, so typing microsoft into the address bar and pressing Ctrl+Enter will take you to www.microsoft.com. Very neat, very efficient, saved me heaps of keystrokes over the years.
It's always been a bit of a pain that there wasn't a way to go to other top level domains as efficiently. Up to now.
Hidden away in the language settings in IE7 is the ability to add another domain suffix to the Ctrl+Shift+Enter shortcut. I've added .com.au, but you might want to add .org, or .co.uk or something else that's relevant to you. The only problem is that it's a real pain now when I go to someone else's machine and this shortcut's not set up (a bit like using a mouse without a wheel, or an operating system without a search bar in the start menu).
In IE 7, go to Tools|Internet Options.
Click the Languages button and set the suffix to the domain of your choice.
Now the Internet's your oyster (if it wasn't already).