Opera, although I keep a copy of IE for the occasional website that has a hissy fit with Opera (partly due to me setting Opera to be quite restrictive about security).
You might want to try configuring Opera to lie to websites about its identity (
File,
Preferences,
Network,
Browser Identity.) This will often enable you to view sites with Opera that don't appear to work otherwise -- usually because a bit of dynamic content programming that goes something like:
if browser == "Internet Explorer" do interesting_stuff
else print "This site is best viewed with Internet Explorer
Version one more that you have now.
Please upgrade"
Often, the site displays perfectly OK anyway...
Of course, this would help perpetuate the myth that the entire world uses Microsoft...
