ASON and AltScript by Carl Sassenrath (REBOL Creator).
ASON is what JSON was supposed to be. It provides an extended set of data-types written in a natural way, the concept of symbols (variables), a cleaner leaner syntax, machine-independent executable expressions, and lightning-fast parsing input to your favorite programming language.
AltScript extends the ASON data exchange format to execute data as code, greatly amplifying its semantic power. It can handle variables, objects, functions, namespaces, and a wide range of expressions in a safe and secure manner.
From my comments about Web Browsers as document viewers:
Alan Kay also argues that sending programs (rather than data structure) is an extremely good idea (based on his experience with JAM – later became PostScript).