MacinCloud - MacinCloud is a Mac cloud platform that provides on-demand Mac cloud servers, flexible dev workload infrastructure and comprehensive Mac in the Cloud solutions
muted.io - A magical collection of interactive music theory tools & visual reference pages for musicians and music producers
XCodeClub.com - Rent your own private Virtual Mac with latest XCode.
Chordify - Chordify turns any music or song (YouTube, Deezer, SoundCloud, MP3) into chords.
VirtualMacOSX.com - vmOSX -- is your affordable, Mac-based home on the web.
Scale Heaven - Browse and play any scale/chord, chord progression.