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.
Be Focused by XWaveSoft - Simple Pomodoro timer in your Mac's menu bar
Noizio - Feeling that the noise of the big city is too much for you to bear?
Effortless - Stay focused and beat procrastination on your Mac.
A Soft Murmur - Ambient sounds to wash away distraction.
Memory by Timely - An intelligent timeline of everything you did in a day.