You can definitely create a web bot with python. It doesn't require that you "drive" A real web browser. There are libraries to open web pages, scrape their contents, and do downloading. That would make your bot platform neutral. Driving a GUI browser has the risk of being a brittle script that might not handle different browsers, different platforms, maybe even not handle different versions.
I run a mediawiki web site, and found a handy python-based library written to manage it called pywikipediabot at http://sourceforge.net/projects/pywikipediabot/. Okay, this library won't do your leg work for you, but it has pieces and parts that demonstrate how to use python to surf a web site. Then, with an HTML parser, you can hunt down images. Greg -- http://mail.python.org/mailman/listinfo/python-list
