FlashToHTML5 replaces the CPU and memory hogging YouTube Flash Player with a HTML5 player.
Not only will it look nicer, you will also notice that your computer will run cooler and faster. If you use a laptop, you will also notice that the battery life of a fully charged battery will increase.

FlashToHTML5 will also automatically load the video at the highest quality available, WITHOUT advertisements!
The only downside is that subtitles and user-captions are not displayed, but that's something I may add support for in the future. ;-)

IMPORTANT: I cannot be held responsible in any way for the possible consequences of using FlashToHTML5 or any of my other applications.