I suggest that you attend dressed as Levi Woodbury, Secretary to the US Treasury 1834 -1841.
It should be a relatively simple costume and there is very little chance that anyone else will choose the same character. You'll probably win over a lot of people with your knowledge of the history of the treasury, especially if you learn a few lines such as 'You can't blame me for the collapse of 1837!' and 'the Second Bank of the US sucks!'
Or failing that, you could go as his predecessor Roger B. Taney. Or Spider-Man.
Edit to add: I got the dates wrong. corrected.
500/363/573 @ 220 belt only
Last edited by Tannhauser; 12-24-2012 at 03:09 PM.