Several times, when I try to return to my session after the screensaver has been on for awhile, it stalls for about 30 seconds, then the spinning wheel that you see when you turn the computer on shows up and all of a sudden I'm back at the login screen. When I log back in nothing is open anymore, but if I try to open Firefox it says it can't because a copy is already open. Does anyone know why this keeps happening and what I can do to get back to my original session, instead of opening a new one? Right now all I can do is restart so that I can open Firefox again. I really wish OS X had a switch user feature...