I am thinking of developing of woocomerce plugin.
Use case.
User may pay their woocomerce purchases using their NXT balance, after the blockchain confirmation it will throw result to woocomerce that an invoice is paid.
Problem.
There's no API to generate a unique address for each payment
Creating an account is not a cheap operation as we need to keep the state of it forever. That's the reason why there's a fee for a new account. It is not recommended to generate a new account for each payment. Instead, add a nonce code as a message to the transaction to identify each payment.