My other computer also has a webserver but it's only accessible from inside Stanford due to the firewall
I find that these centralized servers have quotas, restrictions, downtime and other annoying things. I can run my server as I like, when I want and do what I want, which is certainly nice.
I am also a strong believer in the web as an information medium, not a content medium. So while all sort of picture formats are not important to the web they are a big selling point with the people making the purchasing decision thus they are in most systems. As Prof. Cheriton noticed today.
I am an infomaniac, information gatherer, etc.