you could make recessed cup holes. there good for when your really drunk cause you cant tip over the cups, but they limit your re-rack options a little.
you could laminate photos on it.
you could put a bartop finish on it over bottle caps, or any other stuff you want on it
I once played with some bull riders and they had a table that had copenhagen tin lids recessed into it to set the cups on.
i also once played on a table with a laminated nudie poster on it.
the possibilities are pretty much endless, but whatever you do make sure it is waterproof, and sufficiently braced so some drunk leaning on it doesn't interrupt play, or worse, break the table.