An x64 processor is screaming along at billions of cycles per second to run the XNU kernel, which is frantically working through all the POSIX-specified abstraction to create the Darwin system underlying OS X, which in turn is straining itself to run Firefox and its Gecko renderer, which creates a flash object which renders dozens of video frames every second.

Because I wanted to see a cat jump into a box and fall over.

I AM A GOD.
