The stuck Spirit rover had it's 2000 day celebration recently, and now it's Opportunity's time for it's 2000 sol anniversary. Opportunity has been stopped for a while poking, sniffing and looking very closely at the "Block Island" meteorite found a while back just sitting out in the open on the open plains of Meridiani Planum. The rover is still working it's way across to the big Endeavor crater and is currently 4.2 km into it's 19km journey.
A poster celebrating the rover's 1,910 days past warranty expiration is shown below. Be sure to download the full image to read the poetry.