If you're like most people on the planet, you don't have a Mac. Now before the Apple fanboys work themselves into a rage, just face the fact that you are in the minority. However, just because you're in the minority, doesn't mean that we shouldn't develop web pages that don't render well in Safari, Apple's default browser.
That's where Browser Camp comes into play. It's a 100% free website that will generate snapshots of what a website looks like in Safari. This gets us a good idea of how web pages look in the browser, without having to shell out money for a Mac. Here's a link to a snapshot of my main website. I don't know how often it does a purge of all the images it creates, but with any amount of luck it will be there for you to look at. Looks like purge time is within 24 hours.
While this doesn't allow us to do a lot of full blown testing with Safari, BrowsrCamp does have a system where you can remote into a system using VNC to be able to do full scale testing in Safari for a nominal fee.