I just use Wifi Tether for Root Users from google code... works better than Barnacle or anything else on the market anyway
but honestly, we own the phone and we pay for the data, why does it matter how we use it? Verizon's "unlimited" data plan will throttle your speeds if you go above 5GB and their new plans don't offer unlimited data, they'll charge you ridiculous overages for going above 2GB. It doesn't effect Verizon at all if we use our 2GB a month tethering wifi to our laptops or on our phones, other than that they don't get to charge us 10$ for something that shouldn't cost money anyway.
Screw 'em
It matters because Verizon can show better profits to their stock holders if they charge you twice for the same data. And because we signed a contract saying that it is ok to do it, they can.
Kinda like signing a contract that they can kick us in the stones. Crappy deal for us, but we agreed to it so we can't really blame them for doing it.
That said, free tether away. I pay VZW $130 a month for a single line and data plan and if I want to tether once in a blue moon, I will. I about 2GB a month on an unlimited plan, most of that from Netflix when I am on the elliptical at the gym. If I need to check my email or send a file from my work laptop from the road somewhere once every other month, I am gonna do it and Verizon can kiss off.