Vernal Fall Spiral
See the "spiral" that seems to be spinning at the lower left of Vernal Falls? I didn't see it when I took the photo, but noticed it later, and many people commented on it when they saw the photo in my slide shows in the Valley.
One of the amazing things about the waterfalls is that they have very interesting and subtle changes from moment to moment, and a lucky press of the shutter might just capture a real surprise.