There are a few ways to see Yellowknife without actually going there.
The first is a webcam situated in Old Town, looking out toward Great Slave Lake. You can see that here. **EDIT (03 January 2013): This webcam currently isn’t working. I don’t know who owns it, so I can’t go knock on their door and tell them to put it back up. Otherwise, believe me, I would!
The second is the Canadian Space Agency’s AuroraMAX camera, which captures the entire night sky. You can either watch it live during at nighttime, or watch replays of last nights northern lights. To watch last nights replay, go here.
I’ll definitely be taking some videos once I get up there!