@boomspot
You didn't ask for help solving the problem, but that's why most people make posts about problems. Yeah, I can see how that would be annoying, so if you're just looking for sympathy, there you go.
So, just in case: What OS version are you running? Have you installed anything new recently? Can you think of any changes you made to any settings just before this freezing problem appeared? Does it happen while interfacing with the same app each time? Can you identify any pattern to the behavior? Maybe it's not random after all. You have to provide some clues if you want help. We can't see your screen.