GroupOffice is a groupware suite that takes your office online, implementing online collaboration and CRM. It allows you to share projects, calendars, files and email online with co-workers and clients. It is easy to use and fully customizable. It also features synchronization with PDAs and Outlook.
aria2 is a utility for downloading files. The supported protocols are HTTP(S), FTP, BitTorrent, and Metalink. It has a powerful segmented downloading ability, downloading a file from multiple sources and multiple protocols and utilizing your download bandwidth to the maximum. It supports downloading a file from HTTP(S)/FTP and BitTorrent at the same time, while the data downloaded from HTTP(S)/FTP is uploaded to the BitTorrent swarm. Using Metalink's chunk checksums, aria2 automatically validates chunks of data while downloading a file like BitTorrent.
Open Administration for Schools (OAfS) is a Web-based school administration package. Open Admin does demographics, attendance, discipline, report cards, and has an online gradebook and parent viewing function. It is designed for elementary, K-12, and high schools. It generates plain HTML and uses LaTeX for PDF generation. It also includes special education and division-wide central office modules (all schools run on the same server with different virtual sites; two sites per school, one for teachers, and one for the office). Parent functions are by separate parent/school site.
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.
KeePass is a light-weight and easy-to-use password manager that removes the need for you to remember many different passwords and makes it more feasible to use different passwords for each account. It manages your passwords in a secure database encrypted with AES and Twofish, which is locked with one master key or a key file.
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.)
BleachBit deletes junk to recover disk space and maintain privacy. It rids your system of old junk including cache, Internet history, temporary files, unused locale files (better than localepurge), logs, and cookies. Designed for Linux systems, it wipes clean 50 applications including Adobe Reader, Bash, Firefox, Flash, OpenOffice.org, Opera, Real Player, Skype, and more. It shreds files so that they cannot be recovered, and it wipes free disk space to hide insecurely deleted files. It offers both a simple PyGTK GUI and a command line interface for automation.
Siam Quantum (SQ) is a quantum chemistry program that calculates wave function and total energy of molecules. It currently supports Hartree-Fock and MP2 methods using Gaussian-type basis functions. Geometry optimization is also possible. The source code is well documented because it was initially designed for academic purposes so that students can easily understand. However, Siam Quantum can also produce high quality results for research purposes because the energies calculated are comparable to the ones produced by other software packages such as Gaussian or GAMESS, with the errors in the order of 10^-6 Hartrees, which can be further reduced with more strict cut-off.