A Quote from Portal 1
GLaDOS
While it has been a faithful companion, your Companion Cube cannot accompany you through the rest of the test. If it could talk - and the Enrichment Center takes this opportunity to remind you that it cannot - it would tell you to go on without it, because it would rather die in a fire than become a burden to you.
More quotes from Portal 1
Momentum, a function of mass and velocity, is conserved between portals. In layman's terms, speedy thing goes in, speedy thing comes out.
Well, you found me. Congratulations. Was it worth it? Because despite your violent behavior, the only thing you've managed to break so far... is my heart. Maybe you could settle for that, and we'll just call it a day. I guess we both know that isn't going to happen.
As part of a required Enrichment Center protocol, the previous statement that we would not monitor the test area was a complete fabrication. We will stop enhancing the truth in three... two... zzzt
The Enrichment Center reminds you that the Weighted Companion Cube will never threaten to stab you and, in fact, cannot speak.
When I said "deadly neurotoxin," the "deadly" was in massive sarcasm quotes. I could take a bath in this stuff. Put it on cereal, rub it right into my eyes. Honestly, it's not deadly at all... to me. You, on the other hand, are going to find its deadliness... a lot less funny.