When you see all the garbage on television, something hits you and you start watching all of the old shows you watched and loved as a child on Youtube. You go on wikipedia to find the names of all the episodes, read some other info and why the show was cancelled. Affects people that are at least 17 years of age, can can last a few days, to weeks.
Or it can go away and relapse later.
I was in nostalgia phase, so I started watching Ren and Stimpy and 30 Minutes of Cartoon Openings from the 1990's videos on youtube.