Chrome extension that solved a couple of everyday problems from a single view:
a. Controlling YouTube. I used to have a hard time finding the YouTube tab midst a bunch of open tabs, and if someone would approach me at my desk (good old days when we had offices with people) I didn't want to open the tab to pause the song (or to play it again, or to go next/previous) so this extension would find the tab and show me a simple UI to control it. I later on extended it to be controllable via a hosted URL which I could put in an Android app. This was helpful because if I had to ever leave the desk and song accidentally played out loud, I can pause it from the phone. b. Controlling Jenkins. I had a bunch of builds running and it was painful to visit and see the status, again, amidst all the tabs.