Unobtrusive and useful Google Chrome plugins for developers

There are zillions of plugins for Google Chrome, and several of them are developer-oriented. However, some of these plugins interrupt my usual workflow, or make Chrome slow and unresponsive, or are simply not well tested and crash.

These are the plugins I've found to be more useful:

• FireBug Light (as good as in FireFox).
• Screen Capture - by Google (there are many screen capture plugins, I just picked this one)
• Resolution Test (another classic, very useful)
• jsshell (Amazing for testing javascript and jQuery)
• Magic Inputs Filler (saves a lot of time of filling forms for testing).
• CSSViewer
• Simple REST client (Build custom HTTP request to test your services)