Down for me, but is it just me or is Google's cache kinda broken? When I click the cache link I get a blank page, and then "waiting for wp.sigmod.org..." at the bottom, which hangs forever. I guess it hits the live site if it doesn't have it in the cache?
Cache page doesn't hang forever for me, had to give it about 15 seconds; seems like it's trying to contact the page for images and eventually gives up and shows you the cache. Clicking "Text-only version" made it load instantly for me (there's not anything of substance but the text anyway).