Instructions:
Clicking on a node in the large viz will display its activation with respect to the input.
You may click and drag the small circles in the large viz to alter network weights.
Try clicking a node and watch how changes to an incoming weight alter its activation function with respect to the activation of the node above.
Once you have trained the network, you can go back to previous states by clicking on the tree that will show up directly below.

This is built on top of Karpathy's demo in his convnetjs library .