[snorlax]

Fido consider the Vivaz as a quick messaging phone, not a smartphone, so they may let you get one. This phone can tether via USB or Bluetooth. The details are on the Sony Ericson support site. You do need a real data plan, not the unlimited browsing plan, but since you have one you should be good.
http://www.sonyericsson.com/cws/support/phones/detailed/useyourphoneasamodem/vivaz?cc=is&lc=is