Ed note: Named roentgenium subsequent to this noder's posting.
It's in the last column of the transition metals on the periodic table, just like copper, silver, and gold. Note that the other three elements get more rare and valuable as they go down - but not even gold comes close to how valuable unununium is. Sure, there's only something like 100,000 cubic meters of gold on Earth, which in the proper perspective is not all that much, but only a few atoms of unununium have ever been made. Given how expensive the scientific equipment to make it is, I'd say it's worth several thousand dollars per atom, at least.
Of course, it's radioactive. So I guess you're better off having gold.
It will eventually have a different name and a chemical symbol, which is sad because Uuu looks nifty and unununium is fun as hell to type.