I watch them on my WP7 HTC Surround phone or my BlackBerry PlayBook device (where I have several dozen chan9 videos waiting for me to watch). The problem with using the PlayBook is I always lose my place of where I left off. I take a screen shot with the minutes played showing so I can remember where I left off, but the Windows Phone is the best, except for its much smaller resolution, which is fine for all but the code example videos. My phone however needs much more than its tiny 16GB of storage. My 64GB PlayBook currently has 44 chan9 or microsoft provided dev vids, and a dozen movies and tv series.
I would use my desktop more often to watch, but its summer time, and my computer produces a lot of heat causing me much discomfort, and wearing my headphones makes it even worse.
I use Media Center to record TV shows, then I convert them and copy them to the PlayBook, or sometimes sync to the phone to watch. Rarely do I watch TV anymore on an actual TV or desktop computer, except for the news.
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