In ancient China, women bind their feet for cosmetic reasons, resulting in them not able to walk without help and walking in a shuffling gait.
Possibly this can be modified such that people do it for less stupid reasons.
Disclaimer: This is NOT a racist remark since I'm Chinese myself and hence entitled to freely judge Chinese customs. NOT sexist either since I'm female as well.
This really comes from an ancient Chinese novel. Imagine during the PCs' travels, they come to a place where the gender roles are completely reversed. What adventures will the PCs encounter in such a place?
A sentiment weapon that is very impressionable in terms of what is right and wrong, akin to a child. Currently, being ownerless, it is not very powerful. However, once it has found an owner, it can provide significant boosts to the wielder in an area or areas the wielder most desire. What adventures will this sentiment weapon go through? How will it develop itself in terms of power and personality?
This tome looks like a haphazard collection of random notes on different types of paper stitched together and bound within a wooden cover. The pages describe all of the 300,000 gods of the world, each in the language of the people who worship them. The book is stored high in the mountains, kept safe by an order of monks. Reading the entire book confers a deep understanding on the nature of the cosmos and access to incredible power. This only works, however, if it is read without translation, meaning that the reader must master each language contained within. The various monks know these languages but there is typically only one alive at a time who knows them all. This monk would be an excellent source of information and/or magic. IF the PCs learn about it; IF they can find the monastery; IF they can convince the monks to help them; AND if they can understand the convoluted riddle given as an answer.