They came in my organic food bin yesterday. They look mostly like green onions, but taste like a mix of garlic and onion.

A little info from Mama Earth Organics:

Garlic scapes, which only appear on the finest hardneck garlic varieties, curl upward as they grow, ultimately straighten, and then grow little seed-like bulbs. Astonishingly, they’re usually discarded before harvesting in the most of the U.S. but are considered a delicacy by most chefs. Contained within the garlic scape is a great deal of flavour, although the stalk never does reach the level of the pungent garlic bulb itself. When the garlic scapes are still in full curl, they are tender and delicious. Anyone who wishes to add the taste of garlic to a recipe that calls for onions will find that using garlic scape will provide enough of a bite to fulfill the purpose of the onion, as well as give the recipe an added dash of aroma and flavour.