I’ve been using Firefox for a couple of years now, because of its support for add-ons such as no-script, which prevents malicious scripts from running if you visit a bad site.
However, unfortunately, I’ve been forced to use IE due to Parcelforce’s stupid courier system requiring it and some bulk printing options in Ebay breaking with Firefox.
So, I start using IE by default and opening multiple tabs. A few weeks later and I’m wondering, why the heck is this PC so slow! Does it need a defrag? Cleanup temporary files? Well, I open up task manager, and lo and behold, each tab in Internet Explorer is using about 250MB of ram! I had about 6 tabs open, plus Outlook, Excel, and 2-3 other programmes so available ram was down to practically nil. This was a surprise as the PC has Windows XP installed with 2GB of ram which is usually enough to make XP fly. I currently have 12 Firefox 4 tabs open and by contrast are using 350MB in total.
Moral of the story… if you need tabs, avoid IE!