That's "CPM" as in "Cost-Per-Martian."
But seriously, following the trail blazed by the MillionDollarHomePage, some smart MIT Course 16 students are selling ad space on the outside of their low-earth satellite to subsidize their project. Launch is scheduled for 2010; mission stats here.
RKG is proud to support this effort and encourage others to do so too. (Disclosure: I'm an alum.) Here's the link to get your own name in space and help the next generation of space scientists.
If you happen to be in low earth orbit in 2010, keep an eye out for out for our ad.