Comment J. River Media Center (Score -1) 64
I use J. River Media Center just for this.
http://www.jrmediacenter.com/
It's got a feature much like iTunes, where you can share your media library over a network. It also allows sorting and tagging of every sort of video file (iTunes is very limited with video files). Simply setting up a media server on one computer will allow you to access that same library on multiple computers.