See: http://zacharyvoase.com/2013/03/06/qr-codify/

qr_codify.py

import sys
import subprocess
import tempfile
import urllib

text = sys.stdin.read()

chart_url_template = ('http://chart.apis.google.com/chart?'
                      'cht=qr&chs=300x300&chl={data}&chld=H|0')
chart_url = chart_url_template.format(data=urllib.quote(text))

with tempfile.NamedTemporaryFile(mode='w', suffix='.png') as f:
    subprocess.check_call(['curl', '-L', chart_url],
                          stdout=f, stderr=sys.stderr)
    subprocess.check_call(['qlmanage', '-p', f.name])

Nice idea.

Could not get the qrencode module to install in OS X mavericks

FWIW, I've put together this little script instead

#!/bin/bash
# Author: Rasmus Stougaard

# requrements:
#  install qrencode
#
#   brew install qrencode

tmpQrFile=/tmp/qr-tmp.png
qrencode -o $tmpQrFile && qlmanage -p $tmpQrFile && rm $tmpQrFile