Volatility is not as important when you have real-time exchanges. You can choose to instantly convert any currency to any other currency of your choice - you can choose your volatility tolerance . In the past, that was an ardous, fee-laden process. Now it is becoming more free & seamless due digital tokens. ERC20 should continue making it easier.
No you don't 'have' to buy bitcoin to buy eth. Coinbase, which is known as the largest fiat-> btc/eth platform allows fiat -> eth directly. But yes, I agree that easy access to eth or btc is not available at the moment for those outside the US or outside the neckbeard community
Could extend this so that file continues to exists as long as any peer who has downloaded keeps their window open. So, I share a file to a friend, he downloads, i close window. His window still open therefore link still valid. Similar to this http://ephemeralp2p.durazo.us/2bbbf21959178ef2f935e90fc60e5b...