From a Buddhist point of view, what are the benefits of supernormal powers?
Just from inferring from the texts, you can see how the Buddhas ability to read people's minds allowed him to teach them exactly what they needed to hear. So such an ability would allow someone greater ability to teach people. I also seem to remember in the dhammapada, accounts of the Buddha using his omniscience, seeing understanding arising in monks minds, to telepathically communicate with the monks who were practicing far away in a forest to give them assurance on their path. So as far as I can tell, these powers are to be used to help others on their paths.