Artificial intelligence researcher Peter E. Hart remembers a time when computer networking was an arcane subject that non-users were still trying to wrap their minds around. In an anecdote sent to The New York Times, he recounts being subjected to an audit of his ARPAnet-linked AI center's incoming bits — including questions about whether any of the 2.5 billion packets arrived with "corrosion or tarnish." It's a tiny, but excellent, piece of early internet history.