It's great to be successful, but sometimes being as huge as Google can make a company lose its sense of humor. Google seems determined not to let that happen, though, and if Terminator references are what it takes, we just have to roll with that.
Hacker News user yueq discovered this killer-robots.txt Easter egg, and I don't think it's hyperbole to say that it’s the best thing ever. Basically, a robots.txt is a website file that gives instructions to automated Web crawlers. This one is saying that neither T-800 (the killer android Terminator played by Arnold Schwarzenegger in the first Terminator movie) or T-1000 (the killer terminator in the second movie) should kill company founders Larry Page and Sergey Brin in a Skynet takeover of Google. But it doesn't say anything about you!
In the ensuing thread, Hacker News commenters point out that the Easter egg may also be a nod to critics who compare Google to Skynet, or accuse the company of developing killer robots because of its acquisition of robotics company Boston Dynamics. They also note other Easter egg robot.txt files from Webfusion and Appcelerator.
Google has other .txt Easter eggs, too, like humans.txt, but it doesn't quite achieve the subtle resonance of killer robots. Well played, Google.