Youtube, we know that it is one of the best video sharing site with thousands of videos uploaded. The videos which are available which are low resolution ones just because of the fact catering to low bandwidth.If you have high bandwidth why now go for the high resolution one just in matter of steps.

In general the youtube gives the low resolution 320×240 videos.
http://www.youtube.com/watch?v=cKx16P686O4&feature=related
Just add, &fmt=6 at the end of the url.
say, http://www.youtube.com/watch?v=cKx16P686O4&feature=related&fmt=6
Now check the resolution and feel the difference.
Then add &fmt=18 at the end of the url
say, http://www.youtube.com/watch?v=cKx16P686O4&feature=related&fmt=18
Now the video will play with high resolution 480×360 MP4 high bandwidth videos with better audio quality.