Moodwill - Create and listen for free to your perfect nature sounds environment with music to help you concentrate, relax, sleep and overall feel better.
Noizio - Feeling that the noise of the big city is too much for you to bear?
Noisli - Noisli is a fantastic background noise and color generator for working and relaxing. Online soothing ambient sounds like White noise, Rain and Coffee Shop.
Defonic - Create a unique sound environment at home or in the office
Silenz - Mix ambient noise in with the music you're listening to
MyNoise - Custom shaped online noise machines. Many Many generic sounds