I've looked at these but they do take up a lot of bandwidth, all I was after was a simple 001235 visitors since blah!!
The problem with the simple scripts that give you the "00687 visitors since xxxx", atleast in my experience, is that they only count page refreshes. I've never tried using them in a joomla based site before, though, so I can't say how well they would work.
I'll do some more digging and see what I can find