In this example we can see a collection of three different videos in order. Each video runs for 20-30 seconds and will automatically switch to the next. You may apply this technique into your own website for displaying HD content via HTML5 video.
Check out Beachfront B-Roll if you are looking for more stock videos. The site has published tons of examples which you can download off YouTube or from their website. Here are links to the examples I have setup in this demo playlist: