Backstory: Podcasts are all the rage and people are always finding new ways to monetize their content. Most typically sell ads but there's a growing space where people are selling early access or premium episodes.
The Idea: A platform for podcasters to sell their episodes.
Deep Dive: You would build a simple platform for customers to upload their podcast content and set a price for certain episodes. You could build advanced features such as limited quantity, coupons and others similar to ecommerce stores. Specific features such as limited play/preview could be developed as well.
You could keep it simple and only integrate with one payment processor such as stripe.
Validation: A quick google search found that people are already thinking about this an using other generic paywall platforms.
Monetization: This is a simple SaaS app where you would charge a monthly subscription fee.