CONV. - Convert YouTube video to MP3, GIF or MP4
Inkscape - Inkscape is a free, open source professional vector graphics editor for Windows, Mac OS X and Linux.
Downie - Video download for OS X. Downie supports at this moment over 1,000 different sites.
Sketch - Professional digital design for Mac.
Yout - YouTube to Mp3 Converter
Affinity Designer - Professional creative software, exclusively for Mac.