Time management through interruption.
A simple timer for time management. Create a list of your most common distractions, and the timer will only increment if you spend more time distracted than productive. The extension fires an interruption alert every time the counter maxes out, discouraging long streaks of wasted time.
Current features include modifiable timer attributes, importing and exporting blacklist site lists, and automatically decrementing timers after periods of inactivity (you weren't online, how could you possibly waste time?).
Anticipated features include syncing your blacklists across devices, some localizations, different types of timer alerts, a UI designed by someone who knows how to make UIs, indicators for banned sites, bugfixes (obviously), and whatever good features users suggest!