One of the benefits of cryptocurrencies that I recently heard at a Bitcoin Meetup that seemed very promising was how they lower the cost of remittances. I've heard remittances be defined as the act of returning a payment you previously accepted, and as the act of sending money across borders such as when immigrant workers earning income outside of their home country try to send money they earned back to their home country. The first definition of remittance benefits from cryptocurrencies because the Bitcoin protocol allows you to program money. Just like web technologies like HTML, CSS, and Javascript allow you to program the information that flows through the web, Bitcoin allows you to program how money flows through a financial system (whether that system be your immediate family, a school system, or a nation). If one could automate the return of payments when certain conditions are met, then much of the accounting apparatus that exists would not be needed. This is difficult to do, though. For instance, If you were a merchant that sold radios and you wanted to guarantee customers that they could return a radio they bought if the transmitter didn't work, how can you programmatically instruct 0.1 BTC to be sent to the customer when their transmitter breaks? You could write broken-transmitter recognition software, but then your remittance system is only as good as your recognition software. Nevertheless, the Bitcoin protocol let's the common person who has the necessary programming skills automate this general type of service.
With regards to the second type of remittance, since the bitcoin network is made up of a bunch of connected nodes that exist all over the world, a computer with internet access is all someone from a migrant-worker-sending country would need to receive bitcoins from a family member working abroad. The industry for this type of remittance is in the 10's of billions, so people are waiting for the regulatory environment to become a little bit clearer before implementing services that do this sort of thing.
In general I think bitcoin makes more sense for citizens in a developing country who don't have trusted organizations like exist in developed countries. If you live in a place where the government can arbitrarily freeze your bank accounts which holds your life savings, then Bitcoin offer the common person the ability to store their money in a trustless system where nobody can seize their value. Unless of course you divulge your private keys, or they physically come to your home and demand you give them your private keys.