What colorful words are used to refer to horses?

Horses are so important to human history that it's no wonder English speakers have come up with all sorts of interesting terms to refer to them. Especially in Britain. Here are just a few:

Nag
Gigi or GG
Hay burner
Mr. Ed (from the TV show)
Beast or beastie
Money pit
Dobbin
Bottle of sauce (Cockney rhyming slang)
Hoss
Critter

And those are just the ones for ordinary horses. Here are a few colorful terms for "useless" horses:

Dogfood
Crowbait
Moose (usually for a big, clumsy horse)
Meat horse

(And any variant on the first and last. I remember growing up angry riders threatening to send their horse "to the hunt" - which I think needs no explanation).

Oh, and a longears is a mule (or sometimes a donkey).