I've had a bug since I upgraded to Leopard, everything works fine for a while, but suddenly I can't open apps anymore, or shut down. I've opened and closed many programs today, but I tried to open address book from a spotlight search and the dock icon just bounced and bounced, I right clicked to force quit and nothing happened, I force quit about 10 times, after a while the icon stopped bouncing but was still unresponsive (no windows open, no blue dot under it). I tried opening terminal to try to force quit it, but same thing happens with terminal, and every other app that isn't already running. (Apps that are already open all work fine, unless I quit them they won't open again). I can't shut down, when I chose it from the apple menu, I get the spinning beach ball for a while, then nothings happens. Soon I'm going to have to press and hold the power button to shut down, I can't see any other way out of this. Anyone else had this?