beav (Binary Editor And Viewer) is an editor for binary files containing arbitrary data. Text file editors, on the other hand, expect the files they edit to contain textual data, and/or to be formatted in a certain way (e.g. lines of printable characters delimited by newline characters).

Quick Image Viewer (qiv) is a very small and pretty fast GDK/Imlib image viewer. Features include zoom, maxpect, scale down, fullscreen, brightness/contrast/gamma correction, slideshow, pan with keyboard and mouse, rotate left/right, flip, delete (move to .qiv-trash/), jump to image x, jump forward/backward x images, filename filter, and you can use qiv to set your X11-Desktop background.

Primus is a shared library that provides OpenGL and GLX APIs and implements low-overhead local-only client-side OpenGL offloading via GLX forking, similar to VirtualGL. It intercepts GLX calls and redirects GL rendering to a secondary X display, presumably driven by a faster GPU. On swapping buffers, rendered contents are read back using a PBO and copied onto the drawable it was supposed to be rendered on in the first place.

qtscrob is a GUI tool which reads playback information from iPods, MTP (aka Plays for Sure) or Rockbox (open source audio player firmware) devices and submits them to an audioscrobbler service, such as "last.fm" or "libre.fm".

Neomutt supports all the features that are supported by Mutt, including POP and IMAP support, SSL encryption and SASL authentication, threading and GPG support.

Avahi is a fully LGPL framework for Multicast DNS Service Discovery. It allows programs to publish and discover services and hosts running on a local network with no specific configuration. For example you can plug into a network and instantly find printers to print to, files to look at and people to talk to.