A computer user that spends most of their time gazing into the computer screen looking for Facebook updates. This person is usually afraid of the stove and plays online games with annoying background music.
Dad: "What the heck is wrong with Pookie? She used to hang out in the family room, now she's in her bedroom staring blankly into her laptop."
Random family member: "Oh, she's turned into a Facebookenstein, dad. Can you tell her to mute that thing?"