What's EAV? Entity-Attribute-Value.
It is mostly used for shopping cart websites where you have
things like Price, Color, etc.
I decided to write something like EAV with Drupal.
Take a look at Meteoro.
A Pomodoro app built with Meteor.
For those who like to work on their productivity.
If you're into Django, feel free to mess with AgriCatch, the engine I've built for Berlin On Feier (events app) that grew well beyond the app, into a general data aggregation library.