Happy Valentine's Day, folks! (Or, Singles Appreciation Day, if you prefer.)

I found an article on Mental Floss that discusses famous love letters, and I thought it might be fitting to post the link today:
Dear Valentine: A Brief History of Great Love Letters

Highlights include:
Presidential love letters (including letters written by Woodrow Wilson to Edith Gault)
Letters from Charles Darwin to Emma Wedgwood
Beethoven's mysterious "Immortal Beloved" letters