The upcoming Russian Phobos Grunt mission plans to grab some soil from Phobos, one of Mars' moons and send it back to earth.

The Planetary Society has arranged to include bacterial samples as part of the mission's payload. Purpose: to test whether or not such organisms can survive the hostility of space. If so, it may provide supporting evidence for the transpermia theory, the idea that life may be seeded from one planet to another, or one planetary system to another via organisms attached to meteors.

Read about it here: http://www.scientificamerican.com/article.cfm?id=phobos-grunt-mars

I think it's definitely a cool test. My only concern is that it may officially contaminate the Martian system.

Prediction: Years from now, some experiment detects bacterial life on Mars or one of its moons. Naysayers declare that it must have been due to the bacterial contamination that somehow got loose during this mission. And then we could never be sure.