Notification Center on my MacBook Pro (10.8.2) frequently stops opening halfway, as seen in the above image, and gets stuck. I can click to remove notifications, but nothing outside of Notification Center responds to mouse/trackpad input (clicking or scrolling). Keyboard input still works, so I've tried using Alfred to bring up Terminal and executing "killall Dock" and "killall NotificationCenter," but killing Dock does nothing and killing NotificationCenter just blanks out the part of the screen that it was previously taking up; it doesn't return control. The only way out is a reboot. I only ever bring up Notification Center via swipe gestures on my trackpad or Magic Mouse, never by clicking on the menubar icon. Does this happen to anyone else and is there a solution or workaround?