Nick, thanks a lot.
Those two things were just what I was looking for - an api to get all the interwiki links, and a way to get just the sizes... I will try to update my scripts when I can. Of course, if someone wanted to include it in core, I'd love it - but I cannot do php. The programming logic is dead simple though.
To the server admins, if I only did HEAD requests to get the size, would it be considered acceptable usage to do five-six head requests everytime I used my script to get a page (ie could I publicize my tool) or is that still too much? Does it spend lot's of resources assembling each page each time, or does it go straight from cache anyway?
Thanks Stian