On one of my recent walks in DGCA I had a Pileated Woodpecker call from a tree, almost right over my head. Their call is loud. When this particular bird called out from over my head, my heart skipped a beat.
I snapped a few photos of the bird from the interesting perspective I had, and then watched as the bird flew to another (very dead) tree. It was then that I realized its call was to let its mate know that it had returned. She emerged from a nest cavity in the dead tree, and he climbed in. Very cool.
Here is one of my pictures of the male (with the red patch on his cheek), taken while looking nearly straight up.