So what movie has these elements?:

1. A sentient supercomputer bent on destruction of the human race
2. A robot sent back in time from the future
3. The phrase "I'll be back"

It's obviously "The Terminator" right?

Well in this case it isn't. It's the 1957 farcical sci-fi movie "The Invisible Boy" featuring no other than Robby the robot:

Robby1.jpg

If you look close there are various FP desk sets (and a bottle of ketchup) in the scene. In another shot there are what appear to be some Morriset desk sets:

Robby2.jpg