Massive solar tides
A planet rotationally locked to a nearby primary and with a very short year might have enormous tides; lots of good ideas for a science fiction story here. It might also experience very high seasonal winds, depending on its polar inclination, obliquity, precession, etc. Also, complete gravitational locking may not be the only possibility. Doesn't one of our own system's inner planets have a weird 2:3 rotational/revolutionary resonance or something of that nature?
