The food, not the email
Spam is a brand name for a canned meat product containing ham, pork, salt, flavorings, and preservatives that are mixed and cooked under vacuum pressure. There are other brands of similar canned pork meat products, but Spam—made by Hormel Foods Corporation—is the original and the best-selling of the brands.
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Possible alternative descriptions are "Chunk, used to grout tiles"
Often used as projectiles for passing cars or to create bizarre sculptures.
One such sculpture is the memorable 'Spambi'. And who could forget the jingle "Spambi! Spambi! It's a meat-product toy!"