Android phone: rooted. Didn't even require hooking up ADB. No ZergRush. Just a kernel image, drag-drop from my Mac to internal storage, boot the phone into upgrade, select said kernel image: rooted, with CWM.
Next step: a custom build that gets rid of the stock bloatware, and the next step after that: roll my own ROM images. So-far, I'm using ROM images downloaded from XDA. But, I've got Samsung opensource for my phone, and I'm getting the SDK and platform tools, along with a cross-compile toolchain setup on my MBP. Wish me luck!
Special thanks (shout out) to +Jocala Jocala
for Exhibit II ROM's, especially the super-simple rooted kernel image.