Firefox And Me

This morning I noticed my laptop was feeling a little sluggish. Checked the task manager and it seems that Firefox was now eating up 650 MB of RAM. A new personal best. I do have quite a lot of extensions loaded: About This Site, Adblock Plus, Add Bookmark Here, Better GMail, CacheViewer, Cooliris Previews, DOM Inspector, FEBE, Firebug, Firefox Showcase, Flashblock, Forecastfox, FoxyProxy, GMail Manager, GMail Space, Google Browser Sync, Greasemonkey, IE Tab, MediaPlayerConnectivity, Nuke Anything Enhanced, Tab Mix Plus, User Agent Switcher, Web Dev, Zotero. However, when Firefox starts, it takes up around 100 MB total, which is not unreasonable. I just question the internal coding of any program that can swell to 6x the RAM with just 10 or so sites open. Someone is not deallocating their RAM after usage, or has decided to attempt to cache the entire Internet onto my disk.