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.
Spotify - Map shows when two people play same song at same time
Noizio - Feeling that the noise of the big city is too much for you to bear?
Last.fm - The world's largest online music service. Listen online, find out more about your favourite artists, and get music recommendations, only at Last.fm
MyNoise - Custom shaped online noise machines. Many Many generic sounds
SoundCloud - Enjoy music & follow favourite artists