Ambient sounds are great for helping you focus and increasing your productivity. Listen to Wikipedia plays a symphony of ambient bells, strings and deep resonant notes that all represent Wikipedia edits happening in real time.
Designers Stephen LaPorte and Mahmoud Hashemi use Wikipedia's changes feed to capture several different types of edits happening right now: additions, deletions, large revisions, and even new users. Whenever a change happens, a note is played based on the type and size of the edit.
Not only is it nice to listen to, Listen to Wikipedia is also fascinating to watch. Bubbles of all sizes appear, displaying the subject of the edit. If you click on it, you'll be shown exactly what was altered. You can include up to 35 different languages to monitor, but the English one alone can see up to 100 edits per minute. You can listen and watch at the link below, or download the app on the iOS App Store.