hmmm.
I figured that the "torque" was necessary to overcome static friction. I havn't studied physics past 2nd year and covered this kind of stuff only lightly, but figured that, once it was spinning, heat would come from the effective torque x speed.
The whole "torque on an unloaded shaft" problem confuses me... an unloaded shaft can't really be said to have anything other than a potential torque, and if it is dissapating power, why can't we observe some kind of heating in the system? The energy has to go somewhere.