So we've all heard of werewolves and (I think) they're kind of cliché. I guess you could say that Equihu are my twist for werewolves.
Equihu
Humans who can turn into horses (and vice versa). They live in the North West region of my made-up land. In the countries of the Dwarves, Zarack/Izang, and the Burgansies. (I'll talk about them later)
Their human form resembles their horse form.
(i.e.)
black horse ---- black human with black hair
grey horse ----- grey human with white or black hair
bay horse ------ reddish/mahogany skin with black lower leg and arms and black hair
Their build also resembles their horse form.
(i.e.)
heavy horse (friesian/draft) ------------------- large/muscular human
medium horse (quarter horse/warmblood) --- fast/lithe human
pony (minature/shetland) --------------------- short/dwarvish human
Other than these differences. Their horse form looks like a horse and their human form looks like a human (except for the color of their skin).
The Equihu are considered excellent spies and are used by both the Dwarves and Zarack/Izang. (These two races have been fighting each other for a long time) Because they are used as spies, many Equihu have died "in the line of duty" and most hide their 'nationality' by staying in either horse or human form.
The Burgansies treat the Equihu with respect and thus the Equihu frequently dwell among them. Sometimes in hiding, sometimes revealing who they are.
The Equihu (female) can only give birth to two (2) children. Once the second child is born the parents separate until both children are full grown. Only then do the two reunite. The father takes the older child while the mother keeps the younger. (in the case of twins there is an exception to this custom and the parents stay together until the first born is old enough to be weaned)
Children can be born as either horse or human (which ever form the mother is in when they are born is the form they are born with -- I may have some title or thing about their birth form. Like Shaz-Horseborn or Shaz-Manborn. I'll have to think about it....)
There is a creature related to the Equihu. Only one was ever born/created. It's name is Vashack and the 'race' was called an Equizack. But I'll post in the other area about him
That's all I can remember of them at the moment. What do you think? (questions, comments, opinions)
So, what do they eat? Do they eat according to what shape they are in? (That would be convenient on quests when there is little food.) Or do they eat for both, like C. S. Lewis' centaurs? Are the ever used like regular horses, or are they treated differently? Are they generally friendly, or do they prefer to be left alone? Do they like people outside of their "race"? 
that'll look interesting)
-- I had to find a place to use that smilie some where 
)