1980. When the only copy my local library has of a game or movie I find interesting that I can play on a device I own (For example: My local library's only copy of Sonic Colours) turns out to be covered in scratches, to the point of unplayability. One copy of Barbie and the Secret Door on DVD seemed like it was just the Universal intro on a DVD (the disc would stop playing at the language selection screen), due to the large amount of scratches.
Oh and wow, I just started the 100th page on this thread. Yaaaay, I guess..