MuseScore
Music notation program that offers a free alternative to professional programs such as Sibelius and Finale
Foobar2000 is a versatile audio player that offers native support for several popular audio formats. It can also play audio files within ZIP and RAR archives without having to extract the files in advance.
PotPlayer is a fast and lightweight multimedia player that supports most popular audio and video formats and can be customized with more than 300 skins.
Caustic 3 is a music creation tool inspired by rack-mount synthesizers / samplers rigs.
Multimedia player for various audio and video formats as well as DVDs, VCDs, Quicktime, Real and various streaming protocols. VLC now has Chromecast support!
Any Audio Converter can extract audio from all popular video formats and online videos, and convert unprotected audio files to a wide range of formats.
Free YouTube Downloader downloads online videos onto your hard drive if you want to view a video offline or convert it into a format that can be stored on a mobile device.
Spytify records Spotify to mp3 without ads while it plays and includes media tags to the recorded file.