Shoutbox

And a note in addition to what Chrono said: Increasing the number even more by means of another tool/addon/patch will almost for certain get you in problems in certain situations. So the limit that Plus! sets in that option is the maximum safe limit you can get (well, almost, but it isn't much bigger).

Rumours are that StuffPlug for Windows Live Messenger (when it comes out), would be able to increase the number even more drasticly. But I have been told (either by TheBlasphemer himself, or either by Patchou, can't remember) that such an increase is sometimes not "safe" and can cause bugs.