• Rachmaninoff was deeply introverted; in his youth his aunt’s family nicknamed him “Я сам” (“Myself”) because he kept refusing help and trying to do everything on his own.
• He always carried a golden watch with him which his teacher, Nikolai Zverev, gave him.
• Perhaps it's really some Russian cultural symbol, but lilacs seemed a recurring motif in his life. He had an anonymous fan nicknamed “White Lilacs” who would give him white lilacs at every single performance or holiday—in the form of wreaths, bouquets, or even (as in one case) a conductor’s baton with lilacs embossed on it. He wrote a piece called "Lilacs", and performed at a concert where lilacs were hung everywhere. Even in modern art and festivals, he's commemorated with these flowers.
• As a young man, he loved Leo Tolstoy’s books. His First Symphony’s epigraph referenced Anna Karenina’s: “Vengeance is mine; I shall repay.” Unfortunately, he was greatly disappointed upon meeting the author. When he performed some music for Tolstoy, the latter asked why music was even necessary -- Tolstoy saw most art as frivolous.
• The composer Alexander Glazunov called him “Sir Gay” (Seriously, I read this in a book)
• Although he seldom drank alcohol, one of his pieces, Rhapsody on a Theme of Paganini, was so difficult that, upon its debut, he drank crème de menthe before playing to soothe his nerves. This became a tradition for him to bring good fortune; even today, I meet pianists who drink crème de menthe this way to honor him.
• Another of his pieces, the Prelude in C# Minor, grew so popular that at concerts, the audience would chant, “C SHARP! C SHARP!” He grew so tired of this he almost wished he’d never written the piece at all.
• He loved cars and named one of his Lorelei.
• He was 6’6” (198 cm.) could stretch his hands across thirteen piano keys. This is reflected in his compositions, which are notorious for having some ridiculously large chords.
• He also spoke German, French, and English, but felt most comfortable speaking Russian, underestimating his fluency in foreign grammar. At times, he'd dodge interviews, pretending he spoke no English at all.