The two spacecraft currently orbiting the two innermost planets are both flying low in their orbits in the final phases of their missions. MESSENGER just performed a rocket burn to raise its orbit slightly, while Venus Express did the opposite.
Earth's polar vortex has been in the American news all week. But we're not the only planet that has one; basically every world that has an atmosphere has a polar vortex. Here are lots of pretty pictures and animations of polar vortices.