The measuring probe — called the Lunar Crater Observation and Sensing Satellite, or LCROSS — will be cobbled together largely from leftover parts from other probes. The mission will cost about $80 million, which is very low budget by space standards.More details at ABC News.
Scientists and engineers are especially interested to find out if ice is mixed in with the lunar soil. The results from an earlier mission in the 1990s, called the Lunar Prospector, suggested a large amount was, especially in the floor of craters near the lunar pole, where sunlight never reaches to melt it.
NASA going book to the moon in 2008

NASA announced today it will sent a rocket to crash into the moon's south pole in 2008. A probe will then investigate what is in it.