I thought this was funny in light of the recent flag burning/freedom of speech debate. http://www.cnn.com/2005/POLITICS/10/26/odd.onion.reut/index.html To me this is crossing a line or two. Satire is way too awesome for government restrictions.
The seal is in the public domain, as is any unclassified government document. As long as it isn't being used to defraud, anybody can use it.