Wow, I wish this didn't cost so much.
The more web development I do (where I'm responsible for the (X)HTML/CSS/JavaScript) the more I have to worry about what my pages look like in different browsers on different platforms. Windows, Linux, Mac with IE, Safari, Opera, and Firefox, quickly lead up to many different platform test scenarios.
While looking around today I found BrowserCam. They have all the configurations already setup for you to test on. This is pretty cool.