I love ponies. They are evil little buggers but I love them all the same.
I used to have a 12.1h grey welsh and he was the devil incarnate but oddly, he was the most amazing confidence builder. He was such a horrid bucker when I got him, I remember going out to a show when I'd had him about a month and every stride of canter was a buck of some description. Thankfully he didn't buck very big very often, and I did manage to mostly train it out of him - but as soon as I was bareback he would buck me off constantly, because he knew I wasn't as secure so I wouldn't get on his case as much.
But, what he DID do that was really quite dirty, was that he had a nasty habit of dropping a shoulder, shying violently, bucking while his rider was off balance, and then taking off in the opposite direction. He only ever did it right on the line between a canter and a gallop, when his rider was starting to go up into half-seat, and I never did manage to break his habit. I strongly feel that it was an evasion, deliberately designed to ditch any rider... he would do it with no warning, and he shot underneath the front legs of a big TB mare once.
It's the only dirt he had in him, he was otherwise such an honest little guy.
I want another pony :P