Given the choice I use Firefox, ergo I'm voting for it. My current computer isn't actually powerful enough to sustain it, though, so I'm using Internet Explorer for now.
I prefer Firefox (yay for tabs!) but it does seem a tad buggy at times. And there are times when it doesn't do things that seem obvious, like letting you rearrange tabs (though I got a plugin to fix that) or allow downloads to stop and restart at a later time. But mostly it's great and it pisses me off when I'm at university and only IE is available.
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Spending as long as I do here, it's easy to forget that Oddworld has actual fans.
Heh, no, because it's not actually 17th Century. It used to be a lot better, but once it got a problem. We got a technician to take it away and fix it, and it came back with less oomph. Pretty weird, really.