Sn0wbreeze version 2.3b1 is now available for Windows users to jailbreak iOS 4.3 running on iPhone 4, 3GS, iPad and iPod touch. Just like PwnageTool for Mac, Sn0wbreeze jailbreak is also tethered for all devices, which means you will have to boot into a jailbroken state every time you reboot your device.
Note: There is NO unlock for iOS 4.3 yet. If your iPhone relies on a unlock, DO NOT update to stock iOS 4.3 yet.
Creating Custom iOS 4.3 Firmware On Windows
Step 1: First up, download all the required tools and files to your Windows desktop:"