FlaCC: Flash C Compiler
Earlier this month Peter Elst posted on his blog about the FlaCC Project. In a nutshell, FlaCC is a way to compile C and C++ libraries to ActionScript bytecode, making code written in the C/C++ languages accessible to Flash. Interpreters for various scripting languages are actually written in C/C++ so this could allow you to port Ruby, PHP or Python into your AIR applications.
This video from Adobe MAX Chicago is enough to entice your imagination:


