Freeware Apps

Quicksilver
Quicksilver is a unique app. It is many different things, app launcher, document search engine, workflow tool, automator etc. At the heart of the app is a search tool that automatically indexes apps and certain documents on your Mac. Underneath this though is a powerful plugin architecture that allows add-ins to perform actions on the results of a search. If you have OS X Tiger and though Spotlight was a powerful tool then you should check out how Quicksilver compares. If you don’t yet have Tiger then you can still download an older beta version that will work, however the latest build requires Tiger.

VirtueDesktops
When OSX Leopard is released next year it is likely that VirtueDesktop will be one of the nice free apps out there that will cease to exist as it will be replaced by Apples Spaces. For now however this is probably the best virtual desktop add on for any platform. It does the nifty Apple screen transition animations to flip from one virtual desktop to another, has the ability to anchor specific apps to specific Virtual Desktops and much more.

iScrobbler
iScrobbler is a plugin for iTunes that uploads details of each track played to Last.fm ( free account required ). You can then login to Last.fm and see your personal music charts, most played artist, track etc.

Plaxo
Camino
Clutter
CoverFlow
CyberDuck
Firefox
Google Earth
iStumbler
OSXvnc
Skype
TextWrangler
VLC
Foldershare

Cheap Apps and Utils

Acquisition
Airfoil
Parallels
Comic Life
iStopMotion
Inquisitor

Not so Cheap Apps