XML Canonicalization (C14N) is useful in some cases such as digital signature.
lxml provides a very easy way to do it in Python. However, the current version lxml 2.1 does not give access to all C14N parameters. Here is a simple patch to improve its C14N support.
Using XML-DSig (XML Digital Signature) and OpenSSL from Python scripts is not straightforward, but there are solutions. Here are a few links to useful libraries and articles.
Updating Windows machines which are not connected to the Internet has always been an issue, especially when it is a new install and there are dozens of security updates to find, download and install.
Torsten Wittrock (formerly Heise Security) has published a very handy open-source tool to make all the process (almost) easy, called "WSUS Offline Update".