Another one of the great moments of a geologist's/teacher's life...watching as a new breakout of lava reaches the sea for the first time. I was in Hawaii in August 2006, and had the chance to walk across several miles of new lava to see what I could of the Pu'u' O'o flow off the Kilauea shield at night. Safety barriers prevented the close viewing of any flows and I was ready for some disappointment. Just about the time I was going to give up and head back to the parking area, other hikers said something exciting was happening another quarter mile down the coast. I arrived just in time to see a new tongue of basalt break out from a lava tube, flow across 100 meters or so of the lava shelf, and then over the edge, into the surf. My camera was one day old, and I was scrambling to find a way to get some decent pictures in the dark with a fading flashlight, but a few turned out reasonably well.
I was overdue back at the hotel (by about three hours or so), and so am lucky to still be married, but what a great moment it was. It both stunning, and yet hypnotic watching the newest rocks on the planet forming in front of me.