Erica Sadun over at TUAW points to a new GUI jailbreak software released by Conceited Software/TouchFree. You're supposed to run this only after you run OktoPrep in 1.1.1 (Also by Conceited Software, OktoPrep prepares the iPhone for the 1.1.2 jailbreak), and then upgrade to 1.1.2. It works on both OS X and Windows, and the whole procedure is said to take only ten minutes. Of course, you'll need to downgrade to 1.1.1 if you already bought an iPhone with 1.1.2 on it, which is discussed in the README.txt file in the zip as well as JailBreakMe.com. You can read more on Erica's 1.1.2 jailbreaking process here.