When you read or witness something so good, either online or in the real plane, that your initial impulse is to 'Like' it, only to realize you are neither on Facebook nor reddit, you are a likehead. Your fix is the crack of the Internet. Mark Zuckerberg is your Walter White. You will be schizophrenic by the year 2015, and like to vomit if away from a scrolling screen for longer than half an hour.
The linguistic disease, of American origin, that makes people habitually misuse the word "like". See the various entries here for "like" for more information on the symptoms.