If you are quick, you just might be able to get the Windows Vista Pre-RC1 version from Microsoft. Released to just a few testers last week, Microsoft is now offering the pre-release version of their PC OS to the public. The download is actually open to anyone, but as Microsoft explains in its invitation, a valid Beta 2 CPP product ID is required to complete the installation process. This is a limited-time offer, too: after 100,000 downloads, Microsoft will close off the test program. The pre-RC1 build-a.k.a. build 5536-was released to technical beta testers last week and reportedly brings substantial performance improvements over the Beta 2 version.