More and more people are using Macs. Little freeware applications abound for Mac OS but not many new Mac users are familiar with some of the best ones. I've put together a short list of some of the more helpful applications I've run across.
Adium
Adium is an instant messaging client that combines tabbed chatting with connectivity to a slew of other instant messaging protocols. It sure beats the Hell out of all those iChat windows everywhere.
VLC
Unfortunately, OS X comes with only Quicktime. With more than 95% of the world running on things other than OS X and Quicktime, a solid investment in a third-party media player is necessary. VLC media player has a simple design that will run any video codec or DVD there is, even broken and incomplete files. Windows users should also check this out.
StuffIt
OS X automatically unzips *.zip files with its own extractor, but you’ll need something for those pesky *.rars and *.bins as well. StuffIt Extractor is compatible with *.zip files and 22 other compression formats.






Not bad. But I think a few key items were missed.
Chicken of the VNC A fantastically easy to use VNC client
Perian Must have codec pluggin that makes quick time work with most video formats.
Flip4mac's WMV Pluggin another must have quicktime pluggin.
Neo Office at least until OpenOffice officially comes out with a good working version for OS X.
They do freeware for Mac?!
No, because everything just works.
That is what I thought. Why would there be apps for Mac when it surely does everything out the box (according to Apple). How strange.
Here's a few other utilities I find useful:

Desktop Manager for pre-Leopard multiple-desktop goodness (but it's not updated anymore)
Coconut Battery to see how much your battery has degraded over time
Bits on Wheels for your BitTorrent needs (and it's pretty)
Azureus > all. ALSO with pretty swarm graphic.
Few more damn handy apps
The Unarchiver all your archive formats in one package that integrates seamlessly.
The Fink apt-get style repository for osx to handle all those linux type programs that work in os x.