In the fall of 2011, NASA is scheduled to launch the Mars Science Laboratory. If everything goes well the rover (pictured on the left in an image from NASA/JPL-Caltech) should land on Mars in August 2012. The principal goal of this mission is to determine if Mars ever had – or still does have – an environment capable of sustaining microbial life.
One interesting – and fun – aspect of this mission is that you can send your name along with the spacecraft to Mars. There will be a microchip on board the rover with the name of anyone who wants to participate. If you're interested just go to the Send Your Name to Mars page on the Mars Science Laboratory web site.