I can set up a drop down menu using validation just fine, but would like to
be able to show more information in the menu than is actually inserted into
the cell. Is there a way to make this happen?

Ex:

The information is a list of GL codes and what expenses they represent.
While I want the user to be able to see the GL code definition, I only want
the GL code number itself to display.

I threw this out to the best Excel developer I know and he is stumped. It
seems like this is not that unusual a need and should have a way to make it
happen. Any advice?