I Take No Responsibility For Any Time Lost: YouTube Time Machine

Alright, go ahead and tell your family you love them, because the nostalgia here will probably cost most of the afternoon if not the entire week. I give you, via Lifehacker, the YouTube Time Machine:

Specify a year, some categories of things you want to remember, find a perfect spot on your couch and enjoy the rest of your Sunday. This is likely the best use of the archive of YouTube ever.