I'm traveling and trying to keep track of the Tour while on the other side of the country, so I've been experimenting with a few options. I first tried to find free feeds of the Tour online but they're often flakey and not in English. I watched the Versus channel on TV when I was around in the mornings but there are frequent advertising breaks and pointless filler pieces telling you the background stories of various riders.
Then I tried the Versus Tracker for $30, but I found the video a bit choppy and since it's all in Flash, it would make my macbook air's fan run like crazy and drain the battery within an hour or two (and stages can be 3-4 hours long).
Finally, I tried the Versus iPhone app for $15, and while just about everything about it is buggy (the app crashes when you try to do various tasks, news feeds don't update, twitter links can't be followed, etc), the Live Tour video playback works wonderfully (and is stable), especially on an iPad. I find each morning I can run it for several hours on an iPad (on wifi) that barely drains 10% from the battery.
Also, the video is a raw feed of the entire race without any interruptions. No ads. No NBC Olympics-style docu-dramas about each rider's struggles. Just plain racing from nearly the start through the finish with Phil and Paul doing play by play.