It's a great question - Marc Andreessen has addressed this question a couple times, and one of his analysis (if I've read it correctly) is that the only "inhere

It's a great question - Marc Andreessen has addressed this question a couple times, and one of his analysis (if I've read it correctly) is that the only "inherent" value in Bitcoin is the value that comes from it serving as a transactional currency. I've probably bought bitcoin about a 15-20 times, and every time for the sole purpose of purchasing something. I didn't care (and the recipient didn't care) whether bitcoin was $0.00001, $1, or $1,000,000 a bitcoin - it was irrelevant to both of us. All we really cared about was whether it was non-volatile. If that's the long term future for Bitcoin (as many people believe it is, and ignoring the value of the blockchain as a contract / consensus based negotiation mechanism for a moment), then the Bitcoin's value will eventually settle on a level that reflects its long term transactional use and "time in flight" - there is a non-zero period of time between when I purchase the bitcoin, and the recipient translates it back into local currency, in which the bitcoin will need to be purchased. Take your total daily transaction volume, and that time in flight - and you start to get a good sense of what the inherent value of bitcoin is. That's the simple story as to why people are comfortable purchasing and holding it - it's going to be the global digital currency of choice, and as transaction volume increases, the value of the bitcoin will increase.