After reading this book, I can foresee my pantry shelves getting even more crowded.
In The Indian Kitchen, Monisha Bharadwaj explains what each ingredient is, its flavour profile and how to use it, then gives at least one recipe which incorporates the ingredient. Of a rhizome called zedoary, she writes that it's closely related to turmeric, is said to purify the blood, has antiseptic qualities, and that a paste of it mixed with cream makes a good face mask. The recipes include hot and sour zedoary preserve and zedoary soup.
Asafetida, she explains, "has a pungent, unpleasant smell … due to the presence of sulphur compounds", and although it tastes awful when eaten on its own, "it is added to most Indian savouries as it can complete the flavour of the dish". Asafetida is used in dishes containing spicy chickpeas and in mild lentil curries.