I saw it on here about 2 or 3 weeks ago, or it was on a page that was linked from here. Anyway, it's a group of researchers in what appears to be a castle or a tunnel and there is a cloud of mist that moves around them for quite a while. They move to another room and the mist is not there, but soon begins to appear.

I appreciate your help in finding this.

Yeah i know the one ....As far as i can remember it's on "Worlds scariest ghosts caught on tape" ....I know this is on youtube or google video.....

That was it. Serves me right for not watching it through to the end when I kept stumbling across this video. Thanks a million.