Recently, space image processing enthusiast Thomas Appéré noticed that Curiosity had taken five photos of exactly the same spot on the rim of Gale crater, identical but for being taken at different times of day. That spot was due north of the rover, so the rising and lowering Sun illuminates the rounded hummocks of the crater rim differently from early morning to early afternoon.
Curiosity has spent the last month sampling and processing dark sand scooped from the side of Namib Dune. The rover has now departed Namib and is preparing to cross the Bagnold dune field, while working to diagnose an anomaly with the CHIMRA sample handling mechanism.
There have been tons and tons of HiRISE images of the Curiosity landing region, and it has taken quite a lot of work for me to find, locate, and catalogue them. This post is a summary of what I've found; after five revisions and updates, it's now version 3.0 of the list.
In the six weeks since my last detailed Curiosity update, the rover has driven to, on, and around a couple of active barchan sand dunes on Mars. They are now searching for a site to scoop and sample sand on the western edge of Namib dune.