It’s not as easy to root some phones running Google Android 2.3 as it was to gain root access to early versions of the operating system. For instance, rooting a Google Nexus One after updating to Android 2.3.3 is a pain in the behind, since SuperOneClick, Universal Androot and z4root don’t work. Fortunately there’s a new exploit making the rounds called GingerBreak.
The tool is relatively new and hasn’t been extensively tested, so if you’re worried about breaking your phone, leaving it in an unbootable state, or erasing data on your SD card, you might want to hold off on using GingerBreak for now. But if you just can’t wait, you can download GingerBreak from the developer’s web site.
Xda-developers forum member has put together step-by-step instructions for using GingerBreak to root a phone such as the Google Nexus One using a desktop computer, the Google Android SDK, and some key utilities including BusyBox, su, and Superuser.
If you’re looking for a simpler method, xda-developers forum member Chainfire has posted an APK file which you can copy to your phone and run on the device. Theoretically it will run the exploit and install su and SuperUser with one click.