Which browser do you use?

Firefox mainly.
But do a lot of testing in both I.E and Safari.

Safari then Firefox. IE for testing.

Firefox. IE only when the site actually requires it.

Firefox, mostly. Sometimes Opera or Flock. IE if I absolutely have to.

I use Firefox on OS X..

Safari 3.0 beta.

Mozilla Firefox 2.0 on my laptop, safari/opera/netscape - for testing purposes and IE to find messed up CSS

Safari on OS X and Firefox (much slower) as a back-up.

Firefox until recently. I just switched to Flock, though. It seems to load faster, supports Firefox extensions, and has some pretty interesting features.

safari most, but its a memory hog so I use firefox when doing CPU intensive operations

Safari 2.0 at home. Firefox at work where I have to use a pc. Also Safari for iPhone (obviously)

safari on iPhone
IE or mozilla firefox on laptop
IE on PC at work

Safari mostly
then Firefic

Safari 3 Beta is primary on my Mac at home and XP PC at work; On Mac Firefox is my secondary, but on XP PC, I go to IE second.

camino!

FIREFOX (mozilla)

From a USB-stick, mostly Firefox (latest musume 2.x build and latest nightly alpha (currently 3.0a8)), latest Opera weekly, Maxthon 1.5.6.42 and latest internal build of Maxthon 2.x, K-maleon

On cellphone: Opera and Opera mini (latest stable and latest beta), lynx (via SSH)

Every now and then:
hv3, OffByone, Lynx , Elinks, Safari/Swift/Konqueror, Networker, Scope, Greenbrowser, AmayaWX, Act10, TheWorld, Oracle Powerbrowser.
old , very old and ancient versions of Opera, Firebird and Mozilla suite, Netscape.

Not as often as I'd like:
Contiki , Aweb, IBrowser, Voyager

Well, that's a list!
Which one do you use for what purpose? I don't know wat to do with all those browsers?!

Generally the firefoxes for google reader except for media-heavy sites which in case usually Opera. Rarely open more than ~50 tabs in FX, hardly ever >100.
Almost all youtube are watched offline with KMPlayer after being saved from firefox (downloadhelper)

With feeds that offer little more than a headline in the feed but I want to read them all, tend to use Opera to open all 40-100+ links at once (ctrl+j), sometimes in maxthon (alt+l)
Ditto for forums I frequent , open all newposts at once.
As a result, often have a few windows open in Opera with 25-100 tabs each. In Maxthon , self-imposed (as in set it myself) limit of 400 tabs, so that Windows itself wouldn't run out of resources (GDI & handles, not memory); Sometimes with special cases, temporarily increase the limit if I want to open a 4-digit number of tabs.

If using a less-than-modern windows machine (< Pentium III / 256MB RAM), the firefoxes with their extensions ( 38 in 2.0.0.6, 36 in 3.0a8pre ) are out the question.

Most of the other ones are just for fun, so much so than none of the x86 browser are even installed on 486DX4 /w Windows 3.11 nor on 286 /w MS-DOS 4.0.

The 8-bit browser/server (Contiki) a few times a decade on real hardware (C64 or C128), the 3 Amiga a few times a year on real hardware, otherwise all 4 tend to be used more on emulators.

Safari 3, mostly, then Camino, Firefox, and Opera sometimes.

I wish Firefox behaved better on the Mac.

Camino. Great little browser. (I use Firefox on occasion for bank stuff and the like.)

Firefox, and sometimes Epiphany.