http://en.wikipedia.org/wiki/Black_pudding
Blood sausage or black pudding or blood pudding is a sausage made by cooking down the blood of an animal with meat, fat or filler until it is thick enough to congeal when cooled. In the West, pig or cattle blood is most often used, sheep and goat blood are used to a lesser extent, and blood from poultry is very seldom used. A legend attributes the invention of blood sausage to an absinthe-induced bet between two drunken Bavarian butchers during the 14th century. ...
Tastes better than it sounds....bit like Haggis