I use SRWare Iron for regular browsing. That's Chrome with some dubious "phone home" code removed from it.
Chrome on my main home PC because last time I looked there wasn't a 64 bit Linux version or Iron.

Firefox when I need the functionality of one of its extensions.
IE, Opera and Konqueror when I'm testing web sites for compatibility with all browsers, but ideally that needs early versions of IE, back to IE6 which some people are still using, $DEITY help them.

Anahata