The SeaMonkey project is a community effort to develop an all-in-one Internet application suite. It contains an Internet browser, email and newsgroup client with an included Web feed reader, HTML editor, IRC chat, and Web development tools, and is sure to appeal to advanced users, Web developers, and corporate users. It uses much of the Mozilla source code powering such successful siblings as Firefox, Thunderbird, Camino, Sunbird, and Miro.
Bitcoin is a peer-to-peer electronic cash system that is completely decentralized, without the need for a central server or trusted parties. Users hold the crypto keys to their own money and transact directly with each other, with the help of a P2P network to check for double-spending.
YAGF is a graphical frontend for the cuneiform and tesseract OCR tools. It lets you open already scanned image files or obtain new images via XSane (scanning results are automatically passed to YAGF). Once you have a scanned image you can prepare it for recognition, select particular image areas for recognition, set the recognition language and so on. Recognized text is displayed in an editor window where it can be spell-checked, corrected, saved to disk, or copied to clipboard. YAGF also provides some facilities for a multi-page recognition.
SyncWall is a basic wallpaper changer with a special feature, the ability to synchronize wallpaper changes between several workstations with a basic (and unsecured) client/server protocol. Each workstation must share the same pool of files, there is no FTP or Internet download. Other interesting features are simple multi-monitor support and the ability to add special effects to wallpaper.
MuseScore lets you notate and compose music easily with your keyboard, your mouse, or a MIDI keyboard. You can print beautifully engraved sheet music or export it as PDF or PNG. You can play your score, transpose it, and save it as audio or MIDI file. MuseScore also supports MusicXML to let you share your composition with other scorewriters. MuseScore is often advertised as a cost effective alternative for Sibelius and Finale.
Quassel IRC is a modern, cross-platform, distributed IRC client, meaning that one or more clients can attach to and detach from a central core, much like the popular combination of screen and a text-based IRC client, but graphical. In addition to this unique feature, it aims to be a comfortable chatting program.
Drivel is a GNOME client for working with online journals, also known as weblogs or simply blogs. It retains a simple and elegant design while providing many powerful features, including support for LiveJournal, Blogger, MovableType, Advogato, and Atom journals. (Systems based off these are also supported, including WordPress and Drupal.)