WinFF is a GUI for FFmpeg. It will let you encode videos easily.
Telepot is a Python client which is the REST wrapper for Telegram API.
Telegram-purple is a Libpurple plugin that adds support for the
Telegram messenger.
tg is a command-line interface for the Telegram instant-messaging network.
This is a plugin for Pidgin that allows you to display LaTeX output in
your IMs.
Farsight 2 is a collection of GStreamer modules and libraries for
videoconferencing.
A Ruby API for interfacing with Campfire, the 37Signals chat application.
Telepathy Farstream is a Telepathy client library that uses Farstream
to handle Call channels.
Mission Control, or MC, is a Telepathy component providing a way for
"end-user" applications to abstract some of the details of connection
managers, to provide a simple way to manipulate a bunch of connection
managers at once, and to remove the need to have in each program the
account definitions and credentials.
A SIP connection manager based around the Sofia-SIP library (formerly
known as Telepathy-SofiaSIP)