#8 On the list of "Top 10 Mac Applications" is Perian.
Have you ever tried playing a video file only to have Quicktime tell you that for it to be played you need a special codec or plugin.
I used to have that problem all the time and it made me go mad! Most people will either download tons of things, trying to find the one that they need OR just use a different media player all together.
Well I'm here to tell you there's a much easier third option. Download Perian.
It allows quicktime to play all types of video files it couldn't play before.
It doesn't make Quicktime as good as say VLC (great media player) but it will make most files work. This also saves you the time of having to say Open With... --> VLC for every video file you want to play.
It you use Quicktime or couldn't before because of lacking the right software, check out Perian.
Perian makes Quicktime just that much better.
Perian Website: http://perian.org/