Naaah. Youse guys is all wrong! It's simply a term for the various barreling times of good old Jim Beam's whisky. "The beamage on this bottle is only five years, while the good stuff is the one with a beamage of 12."

All seriousness aside, I found this at a site called Slangsite.com (Anyone seen this one before, seems to be loaded!)

beamage: The path that the laser of anything takes.
Example: Move that piece of paper from infront of the TV, it's in my beamage.

TEd