Length of a vbulletin page

[wacnstac]

How can I find out on the fly how long in pixels or lines a vbulletin page is going to render? I'd like to add more advertising along a RH column is a page is long, or completely get rid of it if a page is small.

[Dismounted]

I don't think you can accurately measure this, as it all depends on the user's browser window size, etc.

[wacnstac]

Hmm, that would rock if you could.