I just moved from a Windows environment and had to leave behind some great software. But after some searching I have found equally good free software for the Mac OS X. I put together this list of absolutely must have free software for a Mac user. Of all the free software that is currently available on the web, these are the choices I made based on my own criteria.

In my opinion a great piece of software has to meet a few things. First is has to be easy or intuitive to use, secondly is to be able to do the job successfully and third to have a small foot print. I plan on updating this list as I go, so come back periodically and check out what's new on my list of free software for Mac OS X.

AppCleaner - System Utility

AppCleaner is a small application which allows you to thoroughly uninstall unwanted apps. Installing an application distributes many files throughout your System using space of your Hard Drive unnecessarily. AppCleaner finds all these small files and safely deletes them. Simply drop an application onto the AppCleaner window. It will find the related files and you can delete them by clicking the delete button.
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LiquidCD - CD/DVD Recording

LiquidCD is a free burning application for Mac OS X. It supports the burning of data, audio, MP3, picture CD and also burns ISO, DMG, CUE/BIN, TOAST images.  One of my first requirements was to record CD’s and DVD’s  compatible with Windows, LiquidCD was capable of doing this best and in my opinion this is the most reliable and easiest to use.
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CyberDuck - FTP

Client Cyberduck is a open source FTP, SFTP, WebDAV, Cloud Files, Google Docs and Amazon S3 browser for the Mac. It features an easy to use interface with quickly accessible bookmarks. The outline view of the browser allows to browse large folder structures efficiently and you can quickly preview files with Quick Look. To edit files, a seamless integration with any external editor application makes it easy to change content quickly.
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VLC media player - Media Player

VLC is a free and open source multimedia player, that plays most multimedias files as well as DVD, Audio CD, VCD, and various streaming protocols. It is simple to use, yet very powerful and extendable.
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Mozilla Firefox - Web Browser

Mozilla Firefox is the second most used browser worldwide, it uses the Gecko layout engine, which implements most current web standards as well as several features for future proof.
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Quicksilver - System Utility

Quicksilver is a launcher, it will create a catalog of applications and some frequently used folders and documents. Activate it, and you can search for and open anything in its catalog instantly. The search is adaptive, so Quicksilver will recognize which items you are searching for based on previous experience. It also supports abbreviations, so you can type entire words, or just fragments of each. When not in use, Quicksilver vanishes, waiting for the next time you summon it.
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Microsoft Messenger:mac 8 - Instant Messaging

Messenger for Mac 8 Beta provides real-time collaboration between people in different locations. Using your Windows Live ID, you can use instant messaging and audio and video calls to communicate with your contacts.
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TextWrangle - Text/Source Code Editor

TextWrangler is the powerful general purpose text editor, and Unix and server administrator’s tool. At its most basic, a text editor is a tool for simply editing text. You can use a text editor for a wide variety of tasks from cleaning up data, to editing configuration files on your Mac or server, to writing HTML or coding.
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Aptana Studio - Development Tool

Aptana Studio 2 is the world's leading IDE for building open web applications
Why are Web developers world-wide choosing Aptana Studio? They've discovered that Aptana Studio offers unprecedented support for web app development combined with today's popular Web platforms. Aptana Studio is available as standalone tool or plugin for Eclipse the choice is yours.
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Growl - System Utility

Growl is a notification system for Mac OS X, it allows applications that support Growl to display onscreen notification.
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MenuMeters - System Utility

MenuMeters is a set of CPU, memory, disk, and network monitoring tools for Mac OS X.  It places all the monitors on the menubar, making it convenient to glance at once in a while to know what your Mac OS X is up to and how hard its working.
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Xee - Image Viewer

Xee is a lightweight, fast and convenient image viewer and browser. It is designed to be a serious tool for image viewing and management, with a sleek and powerful interface.
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UnRARX - Compression Utility

UnRarX is a Mac OS X Cocoa application that allows you to expand RAR archives and restore corrupted or missing archives using PAR2.
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iTerm - System Utility

iTerm is a full featured terminal emulation program written for OS X using Cocoa. We are aiming at providing users with best command line experience under OS X. The letter i represents a native apple look and feel of the program interface, and an emphasis on complete international support. I personally like using this over Mac OS X Terminal because it allows me to have an even more customizable shell screen which blends with the desktop really nice.
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VirtualBox - Virtualization

VirtualBox is a powerful x86 and AMD64/Intel64 virtualization product for enterprise as well as home use. Not only is VirtualBox an extremely feature rich, high performance product for enterprise customers, it is also the only professional solution that is freely available as Open Source Software under the terms of the GNU General Public License (GPL). See "About VirtualBox" for an introduction.
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