I know there are many rooting scripts and programs out there for various phones, including the NS4G, but I thought I'd take a shot and write my own.
It comes with all components (ADB, ClockworkMod recovery, Fastboot, and Superuser) on the latest versions.
Download the Nexus S 4G Root Tool here!
Make sure you read the readme before doing anything. It comes in both a Word and a non-Word version.
I built this from scratch based on my own NS4G, and have tested it many times, and it works.
Let me know what you guys think!
EDIT: I'm currently working on a hybrid rooting + unrooting tool. It will be written using Visual Basic, instead of a simple batch script converted into an EXE.
It comes with all components (ADB, ClockworkMod recovery, Fastboot, and Superuser) on the latest versions.
Download the Nexus S 4G Root Tool here!
Make sure you read the readme before doing anything. It comes in both a Word and a non-Word version.
I built this from scratch based on my own NS4G, and have tested it many times, and it works.
Let me know what you guys think!

EDIT: I'm currently working on a hybrid rooting + unrooting tool. It will be written using Visual Basic, instead of a simple batch script converted into an EXE.