Because I haven't seen it mentioned here yet (and because it is the only one I own): #Gridcoin
Bitcoin mining is incredibly wasteful in terms of electricity and the associated environmental consequences. Gridcoin uses work/computation done for volunteer computing projects that boost research on things like cancer, Zika, clean energy, astrophysics, protein folding, neuroscience, SETI, you name it. Check out Gridcoin for a cryptocurrency that actually does something important (and has gone up by a factor of 15 or so since March!). #BeyondBitcoin