One might call this a budget baked ham with raisin sauce. Spam was a frequent meat on the dinner table when I was growing up, and many people still enjoy it in all kinds of dishes. This will bring back fond family memories for some.
Place Spam in a shallow baking pan; heat at 350° for 20 minutes. Combine butter, cornstarch and water in a saucepan over medium-low heat; stir to blend. Add sugar and raisins. Cook slowly for 15 minutes, then add juices and grated peel. Taste and add salt to taste. Slice meat and serve with the raisin sauce.