I have come to the realization that Half-Life 2 is a whole lot funnier if you mentally add in "harvester" whenever anyone mentions "the Combine":
Alyx: Dr. Freeman I presume? We better hurry, the combine (harvester) can be slow to wake, but once it is up you will have a hard time taking it down.
A letter: Dear Dr. Breen. Why has the combine (harvester) seen fit to suppress our reproductive cycle? Sincerely, A Concerned Citizen.
Citizen: We better hurry, we have to tear down this camp before the combine (harvester) gets here.
Aylx: We know all about you and Breen. You have been a spy for the combine (harvester) the whole time.
Gordon Freeman, the MIT graduated theoretical physicist hero-protagonist, saving the world from enslavement by a piece of anthropomorphized farming equipment.