Unexpected.

"These pots,” he continued, kicking one of them, “are intended not only to catch the water when it rains but also to produce sleeplessness and unexpected music. I can attest to the fact that each drop that falls in these pots makes a sound that is slightly different from the one before and the one after. I have heard more than five hundred different kinds of rain in this room."

Silvina Ocampo, from "The Prophecies"