I am here quite seldomly only.
I edit czech and english Wikipedia as Reo On for some six years (is it even possible? Common!)
Just One year ago I started also one MediaWiki for my own purposes. It is internal knowledgebase in my workplace, so I will not link it here :). I try to get such an patches and extension witch allow me to be it collaborative tool, but only for the invited ones. (And others should not be able to read it either).
In fact, I got quite some experience with using MediaWiki through the years, but I am complete amateur regarding how to run it or how to run any server any php whatsoever. I am just learning.