Mmm, let's see how good my auditory memory is...
Well, well... Gordon Freeman, in the flesh. Or rather, in the hazard suit! I took the liberty of relieving you of your weapons; most of them were government property. As for the hazard suit... I think you've earned it.
The Borderworlds, Zen, is under our control... for the time being. Quite a nasty bit of work you managed over there, I am impressed.
That's why I'm here, Mister Freeman. My employers agree with me you have limitless potential. They have authorized me to offer you a job! (whee, Gordon is thinking, this is just the type of stuff I want to do EVERY day :roll: )
*scene shifts to G-Man in that trolley thing that Gordon originally arrives in at the start of the game, but flying through a sort of Star Trek starfield*
You've proven yourself a decisive man, so I don't think you'll have any trouble deciding. Just step into the portal, and I'll take that as a "yes." Or, I can offer you a battle you have no chance of winning...
*door of trolley opens, showing a portal thingie*
Time to decide, Mister Freeman...
If you enter the portal, G-Man says "Nicely done, Mister Freeman! I will see you up ahead" and then the credits roll. If you don't enter the portal, you find yourself in a pit full of the big aliens with the bug guns. I tried a god-mode cheat with unlimited ammo once but even if you kill them, you still "lose the game."
edit: remembered a little more.