You may have come across the insanely charming letter that F. Scott Fitzgerald wrote to his daughter, Scottie (read it if you haven't, it's an excellent insight into a man losing the battle against his demons).
He concludes the letter with a list of things to worry about, not worry about, and things to think about.
"Am I trying to make my body a useful instrument or am I neglecting it?" seems a very present concern for a man who was soon to die from heart failure due to alcohol abuse.
That lovely list came to me via Lists of Note, a website devoted to lists great and small, young and old. The website includes everything from a scan of the original rules of basketball to writing tips by the noble and the ignoble.
Even through all that, I have a favorite. A new addition to my collection of the more bizarre traditions of etiquette in centuries past (the things my postage stamps are saying behind my back!): The Ethics of Eye Flirtation, from the National Library of New Zealand:
I particularly enjoy "winking left eye twice -- I am married." Apparently, back in 1891, New Zealanders were wandering around like a bunch of Sheldon Coopers...
Oh tumblr. What would we do without you? (that image c/o sheldony.tumblr.com)