Close & Clean

This app will add "Close & Clean" button to your chrome apps (including the chrome app launcher). When you click the button it will close all currently opened tabs and windows and will clean Chrome caches, history, stored data and so on (depending on your settings). It could be useful, for example, if you work with many sites and want to have single shortcut to close and clean everything at the end of the day. By default it will clear only the cache. It can delete other trash too -- cookies, history, saved data etc. You can define what to be cleaned (along with some other settings) on app's options page (right-click on the icon and select "Options").

Screenshots from Chrome Web Store