"Uh, cameraman...your fly is down."

RBI Machine is a nickname for a player who is mediocre at best with the bat, but gets a lot of RBIs due to an ideal placement in the lineup.  RBI machines tend to get overvalued, because despite its prominence the RBI is a near-worthless statistic for ranking the true abilities of hitters.

The term was primarily used to refer to Juan Rivera, though on occassion James Loney as well.