It's a priority queue. To keep track of your priorities. Use it well.

Try it out at priority-queue.com.

Code-quality-wise, I wrote this before learning to use Browserify/require()/other JS idioms, then refactored it to use them, so the code is a bit of a mess. Particularly, the controller and view layers are deeply entangled.

NB: this does not work very well on mobile. I'll fix that someday.