Metafields + JSON == Love
If you haven't heard about metafields yet then I strongly encourage you to check them out. They allow you to attach data to products and open up the door to all kinds of possibilities
There are several 'types' of metafields, one of the most useful, IMHO is the JSON data type.
Because JSON is structured data, you can now support all kinds of interesting workflows and theme features
Thomas Rondio uses them for a different faq on each product page. He has the merchant provide JSON with questions and answers and then displays it on the product page
Christopher Daniel Dean uses them for a Product Customizer
What are some ways you've been able to use JSON with metafields?