UI Sounds - Learn sound design for user interfaces by example 🎵
Defonic - Create a unique sound environment at home or in the office
Fugue - Free and premium stock music for your videos, games, and UI
Noizio - Feeling that the noise of the big city is too much for you to bear?
Chill N' Sound - Play and mix ambient sounds to boost productivity
Noizer - Ambient sounds like Noisli, but free