A lot of folks are asking for a demo and, you're right. I should have included one. My apologies. I'll get to working on one as soon as I can.
In the meantime, I encourage readers to check out the source for http://www.nytimes.com/interactive/2014/02/02/fashion/red-ca... That's probably the clearest "demo" of PourOver at the moment.
More to come!