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A couple I use all the time

MainMenu
Butler (I can't seem to get into QuikSilver)
AppFresh
Name Mangler
ImageWell
Journier

I use loads of the ones already listed, mainly :
VLC
Firefox
NeoOfice
GimpShop
 
quite a big list of apps i would install on a new Mac but not necessary use all the time.

Chat

Adium - chat client for AOL, MSN, Google Talk etc clients.
Skype - video chat client

Media

CoverSutra - iTunes controller with desktop album art
Final Cut Express
Flip4Mac - QuickTime codec for Windows media
Handbrake - rip DVDs to mp4
MacTheRipper - rip DVDs
Perian - QuickTime codec for DivX, MKV, FLV etc
Shockwave (Intel)
VisualHub - encode video to other formats
VLC - universal video player

Web

Firefox
Coda - website developer

Suites

iLife '08
iWork '08
Office 2008

Professional

Photoshop CS3
MATLAB

Utilities

AppZapper
DiskWarrior - Disk recovery utility
Fan Control - MacBook fan controller
Google Earth
iStat Menus - RAM, CPU, network usage in menu bar
Little Snitch - deny internet access to apps
NTFS for Mac - allow write access to NTFS
Mac Pilot - enable hidden features in OS X
Onyx - maintenace utlilty.
Pacifist - custom install of install packages
QuickSilver
Senuti - iPod restore
Steermouse - third party mouse driver
SuperDuper! - bootable cloner
Transmission - BitTorrent client
Toast - Burning Utility
Unison - unenext newsgroup reader
Xsilmmer - removes space claimed by Universal Binary applications and languages

Virtual Machine
VMware Fusion

Widgets

BigPond Maxi Meter - Telstra BigPond internet usage
Countdown Calendar
iCal Events
iStat Pro - RAM, CPU, Battery etc info
 
here's mine (in alphabetical order):

adium
appdelete
audactiy
auoura
caffeine
catalog
cha-ching
colloquy
disk inventory x
dream diary
google earth
image tricks
mori
neo office
nvu
onyx
overflow
quickshareit
seashore
skim
smultron
superduper
text wrangler
total tunes control
uno
vienna
xtastes
yummysoup!

alot isn't it?
 
Apps...

Reading from my dock left to right...

Firefox
Audacity
VLC
VisualHub
MactheRipper
Photoshop Elements
Pixelmator
Office 2008
iWork 08
RapidWeaver
DreamWeaver
FileZilla
VMWare
SuperDuper
Truecrypt
AppZapper
Remote Desktop Connection
Nessus
nmap/xnmap
 
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