It was renamed to Strict Workflow. (But the icon is still a tomato.) It's a Chrome extension for people who work unsupervised, to keep them honest. I have ZAM and a dozen other websites blocked for 25 minutes (with the red tomato yelling BACK TO WORK) and then I get 5 minutes of unfettered web surfy time when the tomato turns green.
It's a stupid human trick, but it works.