Now, just so you Netscape folks don't get too snooty, let me tell the Microsoft Internet Explorer (MSIE) folks that they can do the same thing with this key combination:

ctrl-n

This leaves your first window open, and then you can go on and select a new thread. Then you can disconnect and read the open threads offline.
They're both good browsers - it's mostly just a matter of taste and what you're used to. The only thing I've bound that Netscape can do that I can't do with MSIE is read blinking text like this:
Joe Offer