Thunderbird is a total redesign of the Mozilla mail component to produce a cross-platform, stand-alone mail application using the XUL user interface language. It has many new features, among them the ability to customize your toolbars the way you want them. a new look and feel with a large number of downloadable themes which alter the appearance of the client, and the ability to add UI extensions.
Atmail is a fully-featured email server and Webmail client, allowing users to send and receive email via a Web browser or mobile device. It has full support for IMAP mailboxes, and an optional email-server mode that uses EXIM as the MTA. Features include a scheduler, MySQL backend support, spell-check, address book, calendar user preferences, multiple accounts, SpamAssassin support, migration scripts from other mail servers, a customizable interface, an attractive AJAX interface, an optional group sharing Calendar/Addressbook, and an Outlook plugin to sync Contacts/Tasks/Calendar data between a Desktop, Mobile, and Webmail client or other email users.
BallroomDJ is a ballroom music player. It is designed to let the computer choose the music and to be able to play music the entire evening without intervention. It features flexible playlists, music queue management, requests, seeking in songs, speed with pitch control, and an optional audio file organizer. Playlists can have automatic selections based on your choice of dances and how often those dances should play, stops after some number of songs has been played, stops at a particular time, allowing of songs with certain keywords, sequences, and manual selection. Mix all of these in any order and modify them at any time.
The Epoch Init System is an init system for Linux designed with ease of configuration and non-intrusiveness in mind. It has no external dependencies besides libc and pthreads on a Linux 2.6+ system, though a working /bin/sh is suggested. It's suitable for large and small Linux distributions, but was designed with a focus on smaller Linux systems. It's features include a log system capable of recording boot events before the filesystem is made writable, ASCII runlevels, a convenient, single configuration file setup, automatic hostname setting at boot, automatic virtual filesystem mounting (think /proc), PID file support, stuck job killing during bootup and shutdown, integrated color greeting banner support, and automatic service restart support, to keep vital services running at all times.
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.
VyOS is a Linux distribution for routers and firewalls which features a unified commandline interface and a single configuration file, with an API for extending it. It includes BGP, OSPF, and RIP routing protocols, policy-based routing, a DHCP and caching DNS server, a Web proxy, and more. It runs on x86 physical machines and a variety of hypervisors, including KVM, Xen, VMWare, and Hyper-V. VyOS is forked from Vyatta and based on VC6.6 source code.