Ever see a bike on the street that had your heart going pitter-patter? Sarah Raz, of the Adventure Cycling Association, knows where you’re coming from: "I can't even tell you how many times I've seen a beauty of a bike, hand built or all vintage, parked near the post office or my grocery store, and I've just had to leave a love note," she writes.

Grist thanks its sponsors. Become one.

But there's a quick fix for this uncontrollable urge! Raz suggests keeping on hand a pack of Heroes and Criminals bike love notes (pictured above and also available for unicycles). Or print out these spoke cards. Next time you see a hot ride, leave one behind, and make someone's day. Who doesn't want a little affirmation about how sweet their ride is?

Grist thanks its sponsors. Become one.