I've read some pretty positive things about electric assist bikes recently. Here's a Bike Calgary thread where one guy talks a bit about his e-assist fat bike he uses for year round commuting (mid-way down by GenMacSmiley). As you can see on this same thread gas powered ones aren't as warmly received smile. I'm sure there's other info out there ... this is just one I read recently.

Locally, I understand Power in Motion are the guys to go to for this sort of thing and their website seems pretty good for getting some basic info.
_________________________
Victory awaits him who has everything in order — luck, people call it. Defeat is certain for him who has neglected to take the necessary precautions in time; this is called bad luck. Roald Amundsen