The other day Kari Byron tweeted this image of her morning coffee cup, on which someone had written, "If you are who I think you are, thanks for making science cool!" Byron wrote, "Humbled by the sweetness." By the way she is who you think she is, coffee-writer-person—the awesome host of Discovery Channel shows "Mythbusters" and "Head Rush"—and she does make science cool.

What an endearing way to send someone message, right? And it got me thinking -- what if we all expressed our gratitude in such heartfelt but sneaky ways? A thank-you to a thoughtful waiter scribbled on a napkin, or an anonymous note of appreciation to a coworker sticky-noted to a computer keyboard. An unsigned "thanks" slipped in the pocket of a friendly acquaintance. A chance encounter can lift someone's whole day up, and you can be the writer on the paper cup, as it were.

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How to Say Thank You
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