The accomplishments of Leonard Nimoy, who died Friday at 83, are impossible to list in full. He's obviously best known as Star Trek's Spock, but he also had a successful film directing career (including Three Men and a Baby, the top-grossing film of 1987, and Star Trek IV: The Voyage Home, among the best entries of the original film series), hosted the documentary series In Search Of…, and had one the best cameos The Simpsons ever did.
But my defining memory of Nimoy will always be "The Ballad of Bilbo Baggins":
The song — essentially a musical recapitulation of the plot of The Hobbit, but with much better choreography — was originally released as a single in 1967, and it grew into an internet phenomenon long before streaming video became ubiquitous. I remembering seeing it for the first time in MPEG form, shortly before the first Lord of the Rings film came out in 2001. It remains, at least to me, the definitive filmic treatment of the material, far surpassing Peter Jackson's overlong trilogy and the 1977 Rankin/Bass animated film.
Nimoy revived the song in 2013 for an Audi commercial he did with fellow Spock actor Zachary Quinto: