I noticed Safari was a little sluggish the other day, and found that it was sucking up something like 90MB RAM. And I was just browsing casually. So I started using Firefox, and found it to be doing the same thing-- that is, taking up a lot of RAM. It seems all the browsers I've tried--Safari, Firefox, Camino, OmniWeb--are using unGodly amounts of RAM after very short periods of browsing. This is a recent thing. I haven't installed any OS updates before this started happening or anything like that.
To give further information concerning Safari (since that's what I use most), RAM usage goes up by about 3MB every tab I open, and doesn't go away when I close the tab. It's really annoying.
I cleaned the browser cache, bookmark icons, etc. but that didn't help.
12" PowerBook Rev. C / OS X 10.3.8