Craig Biggio is a former major leaguer who spent most of his career as a second baseman for the Houston Astros.  He also hit 668 doubles in his career.  That's a lot.  More than anyone except for Tris Speaker, Pete Rose, Stan Musial, or Ty Cobb.  Rose spent some of his time playing 2B but he kinda bounced around a lot, whereas Biggio's occasional spots as a 1B or C were greatly overshadowed by the time he spent playing 2B.  The point of all of this is that he could fairly be called the double bag king of double-baggers.

I've only hit a couple of them, myself.  Vancover-based Silver Wheaton Corp. was one of them.  The precious metals bug is still running rampant and everywhere you turn, from your television to internet chatrooms, you'll find scores of pitches for gold, silver...even copper bullion rounds...

http://www.xtranormal.com/watch/8237507/copper-bullion-rounds (don't you dare call 'em pennies)!

http://www.xtranormal.com/watch/8240029/pennies-from-where

Anyway...you'll be able to ride the gravy...er...silver train for some time to come still.  Confidence 10.