Here's a list of some really cool, useful Mac Apps which I use almost on a daily basis in my workflow. Maybe these will come in handy with you as well?
Teleport
Teleport lets you use a single mouse and keyboard to control several Macs. Simply reach an edge of your screen, and your mouse teleports to your nearby Mac, which also becomes controlled by your keyboard. The pasteboard can be synchronized, and you can even drag & drop files between your Macs.
Aptana
The world's leading IDE for building open web applications.
Camino
Camino is an open source web browser developed with a focus on providing the best possible experience for Mac OS X users.
Cyberduck
Cyberduck is a libre, open source FTP, SFTP, WebDAV, Cloud Files, Google Docs and Amazon S3 browser for the Mac.
Growl
Growl lets Mac OS X applications unintrusively tell you when things happen.
Skype
Voice and video calls to anyone else on Skype. Conference calls with three or more people. Instant messaging, file transfer and screen sharing.
Thunderbird
Open-source email management software.
YemuZip
YemuZip is an easy-to-use application for making zip files. Just drag, drop, name your zip file and you're done.