In order to test the capability of the html5 video tag I've used a small portion of the movie Home realised by Yann Arthus Bertrand in 2009, copyright Europa Corp, publicly viewable on many web sites.
I've added a specific page with all the disclaimer and additional informations.
The next one works fine and embeds home 5 min HD_8000.mp4 in progressive download
It is quite useless to show a webpage embedding a 1080p video because its 1920 pixel would be greater than the greater part of common display. So, please, double click over it, it will open in full screen. (double click again to go back to the web page)
Many other true streams can be opened as proxed by Apache, and between the many http://22.214.171.124:80/home_1080p a HD h264 video with a MPEG1 layer 3 (mp3) stereo or the same segment but with the resolution of 720p, still compressed in h264 is also recallable (but not embeddable in page) http://iginomanfre.it/home_720p_5000 as TS stream at 2.7 Mbps or as http://iginomanfre.it/mpg2_6.4_5000.html compressed in MPEG2 VBR as Transport Streams with a peak of 6.4 Mbps and as http://iginomanfre.it/mpg2_4.3_5000 with a peak of 4.3 Mbps.
The reproduction of this kind of content could suffer of continuity problem due to the connection bandwidth or the computational power required to decode it, see here