The Dawn mission has been orbiting the asteroid Vesta since July 2011. It's taken thousands of images of the 500 kilometer-wide (300 mile) rock since then, and JPL just released an amazing video which uses real data from Dawn to simulate flying over the asteroid.
Wow. The animation at Marcia Crater (the bottom crater making up the Snowman triple impact) is especially beautiful and realistic!
Dawn is scheduled to leave Vesta in August and then take a long, slow voyage to the even-larger asteroid Ceres, arriving in 2015. So we still have several months of riveting images of Vesta to look forward to.