Safari has some browser market share and while it's tempting to just put it in the "ignore list", with IE 5 or old Netscape versions it's usually a good idea to test your websites in it too.

Testing on Safari is not easy when you're developing on a PC. You can run MacOS X with Pear, but this is slow as hell. You can buy a Mac. That's expensive unless you do not plan to switch to it. You can bug your friends with a Mac or you can use one of the online services that take screenshots of your website in various browsers and platforms.

Since the rendering engine, WebKit, is based on KHTML, some people use
Konqueror to test their websites. This works, but not fully since Apple modified KHTML so there are differences. And unless you want to try to install Konqueror on Windows using Cygwin, this is not an option.

At some point Apple opensourced WebKit and people started porting it to Windows. Some guy took the source and created Swift, a Windows browser based on WebKit. The project died soon, the websites of the project as well leaving us with a alpha version, with lots of bugs and missing features (scroll wheel support, password input rendering).

While not good at all for day to day usage, it manages to make it easy to quickly test your layouts in "Safari" when using Windows.

You can get the kit here: Swift_0.1.msi. It will probably fail to install properly as the registration of WebKit.dll will not succeed. You'll need to install the NET 2.0 Runtime and this you'll need to manually register the dll with regsvr32.exe.