audio convert is a script that converts between WAV, Ogg, MP3, MPC, FLAC, APE, AAC, and WMA files. It has an easy-to-use interface that makes it possible to fill in the tags for a few formats, copy the tags from input files into the new files, and choose the quality of compression. The script was initially designed for the Nautilus file browser and can be easily installed into Nautilus by using the installer provided with the script. You can then right-click on files and choose "audio-convert" from the "scripts" menu. The script is also known to work on rox or directly from a shell.
bitterbpp is a GUI interface that uses MPlayer to convert DVDs to Matroska files. It uses auto-detection and bits/pixel estimates to generate high quality output, features multiple audio/subtitle track capabilities (direct copy and/or Vorbis transcoding), and supports different video codecs.
DVD95 is an GNOME application to convert DVD9 to DVD5 (4.7 GB). It needs no additional packages, since embedded versions of vamps and dvdauthor are included. The interface is pretty simple to use. The shrinking factor may be computed for best results, or an adaptive compression ratio method may be used. The DVD can be converted to a file tree or an ISO file. The result can be viewed in xine, vlc, or mplayer. Burning the converted image is done with third party software. The output can either include or omit the menus in the source.