Sunset over Eindhoven, the Netherlands. I shot it using a 1200mm lens and had to plan carefully, as the sun only sets directly behind those buildings from my vantage point (a high-ish building some 10 miles away) two days per year.
This is a nice sunset, but the real reason I took this shot is to capture a comet. If you click on the image a couple of times to zoom in, you'll see a white smudge left of the New Moon: this is the comet Pan-STARRS that whizzed past the Sun in February/March 2013. The photo was taken from a hilltop near our home in Los Angeles.