Email heat Map

The D3.js library is free and pretty powerful. I have struggled in the past to get it up and running but had a breakthrough today. Here is my email heatmap. This is showing when email hits my inbox. Saturday's @ 5pm are dead. Hours of power are 8AM ,9AM and 3pm.

You can check out the library here: http://d3js.org/. They have tons of examples and such.