I often explain the value of bitcoin as the protocol and network. That to me is one of the values often missed by the casual observer. The functionality of Twitter for example isn't the main value. Its the network. You could clone the code and you'd have something but no where near the value of Twitter.

The protocol is the law or rules and the fact that they follow game theory incentives make them valuable.

This is how I typically respond to people asking about intrinsic value.