Michael S. Hart, the inventor of the electronic book and the founder of Project Gutenberg, died this week. Project Gutenberg has his (public domain) obituary. Hart was born in 1947. The last published work to pass into the public domain was published in 1923 and it seems probable that copyright terms will be extended indefinitely such that no published works will enter the public domain again.
Update: Nat Torkington has posted a nice remembrance.