I've used PDA Net with my Bell Vogue and an EEE PC for almost a year (now an Aspire One), and never been hit for tethering charges.
Also very cool? Running PDA Net and Franson.com GPS Gate which can send the GPS signal to your PC. Was going up the HWY 400 streaming a movie and tracking/mapping on Google Earth. Don't worry, I wasn't doing the driving.
