We have had working free wifi tether through the foxfi app. The only thing that is sort of worrisome about using foxfi is that it uses a VPN to hack around the subscription check of the native tether app. This means that your internet traffic could potentially be monitored. In fact after installing and using foxfi to tether on your device you will be warned every time you boot your phone up that your internet traffic is being monitored.
ScottsRoms who is most well known for his CleanRom series has posted his wifi tether hack which can be installed by flashing a zip file through Flash Fire. You will need to be rooted, but this will work on both OC3 and the latest version of Android OE2. Head to the link below to grab the file you need and be sure to flash the proper file for your current version of Android.
via XDA
FlashFire Beta