Haggis, made from pigs.
EDIT: OK, my apologies, I'm being obstructive. Scrapple is what's left over from pigs after you've used about as much as you can from the cuts you want. The "scraps" are then fed into a grinder and puréed. Corn meal or starch is added for texture, and salt and spices to taste.
I've known about it since forever, as it's a staple of the "Pennsylvania Dutch" or Amish/Mennonite sects of Lancaster county - about 50 miles west of Philadelphia. I'm guessing they have a similar "pork by-product" in other enclaves, such as those in Iowa, Ohio and North Carolina.
Slice it thin and fry it up until it's crisp, and it's actually quite tasty.