Though powering .gov websites isn't at the core of the U.S. government's financial woes, certain agencies will take their websites offline if there is a shutdown on Tuesday. Ars is reporting that the Library of Congress, the National Parks Department, the Securities and Exchange Commission, and the Federal Trade Commission would shut their websites off in a shutdown.
Most would put up splash pages, which would be especially important for agencies like the FTC that have already told employees to check their website for ongoing shutdown information. The Department of Veterans Affairs is saying that it will do intermittent updates of its site. A government shutdown has the potential to cause much bigger problems than some 404s, but cutting off information resources is probably not the best way to get things back on track. Too bad servers can't run on patriotism alone. [Ars Technica]
Update: It seems like NASA's sites may go down too, based on this post from the administrator of Astronomy Photo of the Day (APOD). "Although the main APOD web page is served from NASA, APOD is written and edited by professional astronomers who do not work for NASA directly as civil service employees. Therefore, APOD will continue to be updated daily even if the US government shuts down, but will (likely) not be served from NASA during this period."