Firefox

 

Mozilla Firefox is a web browser. It is immune to most spyware and blocks viruses from downloading automatically. It has build in filtering for cookies, scripts, and popups. It has a built in download manager, an automatic updater, supports tabbed browsing, supports program extensions, and many more features.
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Wine

 

Wine is an open source project that allows you to run Windows executables in Linux. Wine allows you to use Microsoft Office (although you should be using Open Office), some games, and a wide selection of applications in linux.
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Open Office

 

Open Office is a direct competitor of Microsoft Office. It is even mostly compatible with Microsoft Office. It has a word processor, a spreadsheet, a drawing program, a database program, and a presentation program. It has many advanced features, like wizards to guide you, spellchecker, autocorrect, and it can save documents as PDF files. And it's free.
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Audacious

 

Audacious is a media player for Linux that is based off of the Beep Media Player, which is based off of XMMS. It can play MP3s, Ogg, AAC, FLAC, WMA, Mpeg3, and several other types of audio files. It also supports several input, output, visualization and effects plugins.
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Evolution

 

Evolution is an office productivity pack, including an email client, an address book, a calendar (that supports the open iCal standard), a to-do list, and Palm Pilot support.
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StreamTuner

 

StreamTuner is a streaming audio browser that pulls station information from Shoutcast.com, Xiph.org, Live365.com, Google, and other sites. When you find a station that you want to listen to, just click on it and it will pop up in XMMS. It has a clean and intuitive interface and allows you to bookmark your favorite stations. You are able to sort by genre, bitrate, and more.
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VLC Media Player

 

The VLC (VideoLAN Client) Media Player is an excellent multimedia player that is capable of playing many different types of audio and video files without the need to install separate codecs (like DivX, QuickTime, and Windows Media).
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Azureus

 

Azureus is a BitTorrent client written in Java. It is perhaps the most advanced BitTorrent client in the world and is an excellent example of how open source can be extremely powerful and configurable and yet remain usable by novice computer users.
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GQview

 

GQview is an image viewer for Linux with features such as zoom, slideshow, a thumbnail view, batch file rename, finding duplicate pictures, an image search, keywords and comments on a per picture basis, viewing EXIF information, and more. It supports most file types as long as you have the required libraries installed.
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Pidgin

 

Pigin (formerly known as Gaim) is a Jabber instant messaging client. This means that it is a chat program that is compatible with the AOL instant messenger, MSN Messenger, Yahoo Messenger, ICQ, and IRC as long as the server you connect to supports these transports. It supports tons of smiley faces, WYSIWYG editing, plug-in support, and file transfer capability.
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Tomboy

 

Tomboy is a sticky-notes program that allows you to link related notes together. This comes in very handy if you use it like a to-do list, as you can explain each item in further detail if you want to. Tomboy allows you to create links to other sticky notes, webpages, and emails. It has an inline spell checker, a few font options, and multiple undo/redo.
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QPS

 

QPS is a graphical process manager for Linux and other Unix like systems. It has a ton of features like graphing CPU and memory usage, renice a process, send kill or another signal to a process, and it can display open TCP/UDP ports that a process is using. I think this program is a wonderful addition to the Xfce Desktop.
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Bastille Linux

 

Bastille is a program that will "harden" your linux system. It increases system security by disabling, password protecting, or changing file permissions on vulnerable files. The authors have done an excellent job of explaining what each step is going to do and how it could affect your system. Much care was put into the default values and you should be able to accept them without causing harm to your system.
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Gambas

 

Gambas is an IDE for the Basic programming language. It has a visual form designer, and so it is the closest thing to Microsoft's Visual Basic that exists for Linux. I will leave it up to you to decide it that is good or not.
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Bochs

somewhat replaces VMWare Workstation

Bochs is an x86 emulator that is capable of emulating computer hardware. If you have ever used VMWare, then you know what this program is. The main thing this program does is allow you to install Windows or another operating system from inside of your current system.
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Revelation Password Manager

 

Revelation is a password manager written for the Gnome desktop environment. It uses AES encryption to save your passwords, it can check the strength of your passwords, and has many features to help you find and organize your passwords into categories. It has unlimited undo, so if you accidentally delete the wrong account, it is not gone forever.
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Qalculate

 

Qalculate is perhaps the most advanced calculator I have ever seen. It has separate GTK and QT interfaces, so it will integrate well with whichever desktop you use. It may take you a while to figure out how to do what you want, but be assured that it will do what you want.
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