The Chaos;Head and Steins;Gate Visual Novels both relate "The Committee of 300" back to CERN, and their plans to take over the world, etc. Also, in the last episode, the girl who comes from JAXA to take away the robotics club members is Mr.Braun's daughter, Nae, from Steins;Gate. Already a solid connection between the two. It freaked me out when I first heard her name. Also, the song "Kagome Kagome" was the ringtone used in Chaos;Head when the "real" Takumi calls the fake Takumi throughout the VN. Which kind of gives me the impression that maybe Takumi was the one to create Airi and is directing our main character in Robotics;Notes. Lots of mystery, lots of references. Me likey.