All that barrel does is stop counterfeiters and tax evaders. Neither of those things are "intrinsic value". And Bitcoin is FAR more difficult to duplicate (you can't even forge or counterfeit it, you have to "double spend" it in a tricky operation requiring owning at least 50% of the network, good luck with that) than any other currency.
Read this: http://bitcoinsurvey.wordpress.com/2013/04/08/what-is-the-re...
Basically, a currency cannot drop to zero value unless ALL trade in it stops. If you think about it, this makes sense. So that is its "intrinsic value". The trade volume props up this minimum. There is of course "speculative value" laid on top of that, but where one stops and the other begins is anybody's guess.