This is an interesting coincidence. I happened upon this a few days ago for the first time and it worked out really wonderfully.

I needed to transfer data from a python script to a ruby script. Ended up looking like this:

Python script:

    import msgpack
    msg = msgpack.packb(some_data)
    sys.stdout.write(msg)

Ruby script:

    require 'msgpack'
    msg = `python my_script.py`
    some_data = MessagePack.unpack(msg)