While USB tethering over 3G/4G networks doesn't work unless you pay for the $30/mo hotspot feature (which I still cannot get Sprint to admit is a stupid name since I don't want a hotspot, only tethering, but I digress), you can tether and use the phone's WiFi connection. Why would you want to? Well, I have a laptop that requires a USB dongle and now I have one less thing to carry. OK, not the best reason, but I found it interesting. I don't claim it's terribly useful.