Rapforthemoment on "My website pages showing error 404 message"

I go to sleep and everything is fine, I wake up and half my site is down with 404 messages. What could the problem be? Here is my website: http://www.rapforthemoment.com :All of the pages except the ones for Buddypress (Activity, Callouts, Crews) are down with 404s. I went into my editor's dashboard and checked out the pages and all the content is there, but once you try to go to the site, nothing but errors.