nasa_desktop.py

#!/usr/bin/env python
# Run as cronjob to have a daily fresh desktop 
# background from the NASA Image of the day gallery.
# You might need to install BeautifulSoup and appscript
#   easy_install BeautifulSoup appscript

from os.path import basename
from BeautifulSoup import BeautifulStoneSoup
from appscript import app, mactypes
from urllib2 import urlopen


rss_url = 'http://www.nasa.gov/rss/lg_image_of_the_day.rss'
image_url = BeautifulStoneSoup(urlopen(rss_url).read()).find('url').string
image_path = "/%s" % basename(image_url)
open(image_path, 'w').write(urlopen(image_url).read())
app('Finder').desktop_picture.set(mactypes.File(image_path))