I found this interesting. A town in Pennsylvania passed a law that would allow them to penalize companies that hired illegal immigrants and fine people that rented houses/rooms to them. The federal judge ruled that they can't do that because that is a job for the federal government (who are doing such a bang up job at it). So if you are unhappy with the job the feds are doing, you can't actually take action yourself and do their job for them.
Here is the story.
http://www.nytimes.com/2007/07/26/us...rssnyt&emc=rss