We have already updated you that Sn0wbreeze 2.2 jailbreak tool with iBooty 2.0 is about to arrive. The tool will provide 1 click tethered boot on iOS 4.2.1. The developer of the tool has posted a teaser video. Interesting thing about the tool is that it allows you to play Pacman game while sn0wbreeze 2.2 builds the IPSW. You can switch between the IPSW building screen and the Pacman game.
From the previous updates we already know that Sn0wbreeze also contains Baseband Preservation Mode in addition to simple mode and expert mode. You can jailbreak iOS 4.2.1 using Sn0wbreeze and later unlock using the Ultrasn0w tool.
For those who are unaware of Sn0wbreeze jailbreak tool, it helps you build a custom .IPSW file on Windows operating system very similar to the process of creating .IPSW using PwnageTool for Mac.
Download Sn0wbreeze 2.2.1 iOS 4.2.1 Jailbreak Tool For Windows OS
Follow the STEP BY STEP GUIDE to use Sn0wbreeze 2.2 on Windows