I love Cross Browser Testing
. It's really exactly what I've been looking for for the last decade.
Using Java or your own VCN software, CrossBrowserTesting (CBT) allows you to connect remotely to a desktop operating system of your choice -- Ubuntu (linux), Mac, and various versions of windows (98-vista) with full administrative privileges. From here, you can test your websites (or software applications) against these other configurations. You can't, on the fly, swap operating systems -- and as such, will find yourself going through multiple sessions to test against everything you need to. But at the end of the day, multiple sessions is a lot easier than cross browser testing without access to everything.
It works great, and if you only need to use it briefly/casually it won't cost you a thing. You can launch free 5 minute sessions as often as you'd like. Free sessions may result in a few minutes waiting in a queue, though, as others are trying to get in. Alternatively, you can purchase credits for around $1 apiece (with discounts when you buy in greater quantities) giving you priority when requesting a session with an OS. No queue and, at 5 minutes/credit you can maintain sessions longer than 5 minutes for more time consuming testing. Finally, there's a monthly subscription option -- which gives you "Unlimited" time for a flat monthly rate. Subscriptions are 29.95 for the first month, 19.95 for all months following -- for a limited time. The prices are scheduled to go up in the future. For a limited time, you can get a price lock in at the 19.95 rate.
Pretending I have a Mac
Within a session, you have the ability to take a snapshot of the desktop's current state, which you can save to your CBT account as well as cross post to flickr. Handy for keeping on hand snapshots of display peculiarities or the output of a debugger. Or making photos for a thread post, ala... these. You can even turn the photos into a slide show
Digg isn't so hot on IE5. FFx 1 handles it like a pro, though
As a web developer, I've found crossbrowsertesting to be a real godsend. I no longer have to search for people with the OS/Browser configuration I wish to test, I no longer need to go through hoops to maintain multiple versions of any given browser; from the comfort of my browser of choice, I can see the Internet as seen from a plethora of web browsers.