Thin slices of Mettwurst, made at least partially of equine meat, are quite a popular sandwich filling in most of Central and Northern Europe. It's not uncommon for adolescent boys to tease their (usually female) horse-aficionado peers with jokes built around this fact.

(Incidentally, horse meat is apparently very high quality - high-protein, low-fat. And of course, equines - gazelles and others - were an important part of our ancestors' cuisine.)