Just a little (but vibrant) flat panel note card that says "just a little note" on the envelope in gold foil. Write on the bright neon side, or on the white reverse side- it's totally up to you.
Keep these bright colored, blank on the inside note cards on hand for all occasions.
'Hello Friend!', 'Like WIne You Get Better With Age', 'This is Kind Of Like A Free Hug' 'Merci (That's French For Thank You)'