jq is a lightweight and flexible command-line JSON processor.
A simple JSON parser library for Processing
Tempo is a tiny JSON rendering engine that enables you to craft data templates in pure HTML.
Javascript template engine
oEmbed is a format for allowing an embedded representation of a URL on third party sites. The simple API allows a website to display embedded content (such as photos or videos) when a user posts a link to that resource, without having to parse the resource directly.
A tutorial on Processing + JSon