Comparing Io to Europa, scientists assume Europa is more likely to host life because there is water there, but that water is likely completely homogeneous in temperature, providing little energy for any life, and even less places for that energy to go.  Io is basically one large Yellowstone. Each of those geisers and vulcanic cauldrons has such a vast contrast in temperature that life may just fluke into existence like it did here.  And those are in my opinion some of the less promising bodies. Jupiter herself is so vast and full of anomalies that there could very well be life in there, too.  So basically, is water essential to life, or is water essential to Terran life.
computers don't need much water at all, do they