DivX HiQ Beta does Flash video better than Adobe
Some people say that Flash video playback can be a tad crappy at times. This is a pretty obvious business oppurtunity for competing video products, and indeed, DivX tries to one-up Adobe with its DivX HiQ Beta 2.
It's a whole (free) bundle of applications, but the interesting one is the DivX Web Player. It's basically a player that latches onto the YouTube player and a bunch of other common video players online, and offers an alternative Play button. When you hit that button, DivX takes over and plays the source video data using its own codec.
Using the DivX codec supposedly yields a bit of a performance boost on slower systems, but caveat emptor: This is still beta. When I tried it, the alternative Play button never showed up on Chrome, and when it showed up on Firefox, pressing it only caused an error message to pop up saying "the video cannot be found". Still, if you have an older computer, you might want to give this one a try (especially once it loses the Beta label).