In the last few days, Opportunity's passed by several craters, and the rover drivers took advantage of the chance encounters for what they call "drive-by shooting" (a phrase I can't say I'm particularly fond of, but they didn't ask me).
Waaaay back when Spirit and Opportunity landed on Mars in January 2004, the Planetary Society helped the public participate in the missions with a number of projects, including one where we printed "secret codes" around the edges of the two names-bearing DVDs that were bolted to the Mars Exploration Rover landers.
Opportunity is continuing to make tracks toward Endeavour crater, but just because she's got a goal for her road trip doesn't mean she won't stop and smell the flowers from time to time. Er, did I say "flowers?" I meant "meteorites."
I've had a fun morning of noodling around learning how to write KML files, and have produced one for Google Mars that shows you all of the Mars Orbiter Laser Altimeter tracks that cross the area Opportunity has driven through already, as well as the area of Endeavour crater.