ID:259813
 
Constant var which returns the resolution the client is using.

src<<browse("Hello World!","window=browser;size=[client.resolution]")
You should put a lot more effort into your feature request posts.

You can get that effect right now with Javascript, by the way.
In response to Crispy
You can get that from javascript? I know you could run an applet that could tell you that, but... I dunno, why would you restrict by screen size? Why not just give a message that says: "X resolution reccommended", if they don't comply, it's on their head.
In response to Ter13
First result on Google:
http://www.pageresource.com/jscript/jscreen.htm

You can send information from Javascript back to BYOND; I've heard of it being done. Haven't tried it myself, but at a guess you redirect the user to a link that looks like this: byond://?blahblah ... which then triggers client/Topic(), and you can go from there.