The squeezebox family from Logitec (used to be slim devices) rocks. It will read all of your music + internet radio stations plus more, available as inexpensive component audio, boom boxes and even high end audio components

They just change the electrolyte. It suffers from all the problems batteries do, they always will.

Furthermore, hydrogen is never found in nature in a purely oxidizable state. The closest thing is natural gas, which is where 90% of hydrogen used for industrial purposes comes from. Using electricity for electrolysis results in 50% loss of energy to heat.