Recently I've been having problems with the built in screenshots in OS X Mountain Lion. Every now and then it stops working, and the only way to get it working again seems to be logging out and back in. Obviously I can use grab, but it can be inconvenient. When I try toggling it using ⌘+⇧+3 or ⌘+⇧+4, I will either get the funk error noise, or simply cause the mouse to disappear. Nothing new appears in the console messages.
I'd be sufficiently satisfied if I could find out what process is linked to these screenshots, so I wouldn't have to log out/in every time I need to take one, but if I can fix the problem altogether that'd be even better.