The ciano is a multimedia converter for all the format you need.
Stellarium
Stellarium is a free open source planetarium for your computer.
ClipGrab
ClipGrab is a free downloader and converter for YouTube, Vimeo, Facebook and many other online video sites.
Audio-Recorder
This amazing program allows you to record your favourite music and audio to a file.
KStars
KStars is a Desktop Planetarium by KDE. It provides an accurate graphical simulation of the night sky, from any location on Earth, at any date and time.
Taime tei tau'a-ore-hia
System restore tool for Linux. Creates filesystem snapshots using rsync+hardlinks, or BTRFS snapshots.
Celestia
Celestia – real-time 3D visualization of space
Kdenlive
Kdenlive is an acronym for KDE Non-Linear Video Editor. It is primarily aimed at the GNU/Linux platform but also works on BSD and MacOS.