Ring of carrying
In xNetHack, the ring changes your carrying capacity by 5% per point of enchantment. Negatively enchanted rings will decrease it and positively enchanted rings will increase it.
In FIQHack, it increases or decreases the wearer's carrying capacity by 50 per enchantment. It can also be used by monsters, and it can be eaten to acquire the effect intrinsically (33% of the time, as per usual ring eating rules).