Right now, ICS via USB on the mogul to my linux box is saving my butt - they're working on my DSL/Phone line, yet I am still online - woohoo!
Bottom line, like everyone else says
* PAM plan is only legal way to do it
* Sprint probably a wee bit safer then VZ for casual PAM use with data plan but without PAM plan, but in either case...
* DON'T GO CRAZY WITH IT
There goes another 2kb of data use