Cursed into the form of a bear.
This is fairly low on the list of curses, because though I imagine it would be pretty awkward, maybe it would be kinda cool sometimes, too? Being all powerful and RAHRRR.
And I mean...you live in an enchanted castle, Bear. What more do you want?
Cursed into the form of a toad.
This should probably be followed by "being forced to marry a brat," cause you gotta admit, Toad's a pretty good toad. He's helpful to the princess. He fetches her golden ball, she runs away. He wants to be cuddled, she throws him against a wall. Would you want to marry that?
Forced to dance all night in an Other realm...
...which is both a curse and a blessing. I've already mentioned how much I want to see the underground world of The Twelve Dancing Princesses, so I might be willing to put up with a few blisters to do so.
Having bugs/toads/various other insects and/or amphibians/reptiles spill from your mouth when you talk.
Similarly, being 'blessed' with gemstones and coins, etc. Both of these just seem damned inconvenient.
Silver Birch, Blood Moon. You should check it out.
Wouldn't be so bad if it weren't for all the creep-os lurking in the shadows, waiting to...do stuff.
Not that I think glass shoes would be so comfortable, and HOLY HELL, what if you landed none-too-lightly on your feet during a dance step? But iron shoes, meant to be heated over a fire and then placed on the (assumedly crying and sniveling) wearer, who is then made to dance until the shoes cool (or you know, they die)...that is some next level sh*t in the realm of curses, ya know? Probably because, unlike many of them, they seem totally plausible to our world
Pecked out eyeballs.
Look, I'm not saying they didn't bring it on themselves, but Cinderella's stepsisters have clearly already had to put up with a lot in their lives — their mother makes them chop off their respective toes and heels in order to fit in a pair of shoes, and I highly doubt this was the first odd and painful thing she'd made them do. But as punishment for their sins against Cinderella (which my tired fingers just tried to spell 'cin,' so clearly it's time to call it a night...), they had their eyes pecked out by birds.
AS THEY WALKED THEIR SISTER INTO THE CHURCH ON HER WEDDING DAY.
I mean... dude.
So what are some of your favorite fairytale curses or punishments?