In Vault 87, if you go retrieve the G.E.C.K yourself, you fill get the three options. One is about activating it, one is for taking it and the third one is the typical "Nevermind." option.
When you choose the activate choise, you get another window asking about it. And again. And again. And this time, if you choose activate, a blue ball of energy expands, KILLING you INSTANTLY. That's what it's about.