pyratemp is probably (one of) the smallest complete template-engines for Python (with about 500 LOC). It has a very small set of special syntax in the templates. This reduces complexity and the probability of bugs and lead to an easy-to-use and intuitive user-interface. It uses embedded Python-expressions (in a "sandbox"), is well documented, has full Unicode-support, and produces very good error-messages, which is very useful when creating new templates.
PottyMouth transforms completely unstructured and untrusted text to valid, nice-looking, completely safe XHTML. PottyMouth is designed to handle input text from non-technical, potentially careless, or malicious users. It produces HTML that is completely safe, programmatically and visually, to include on any Web page. You don't need to make your users read any instructions before they start typing. They don't even need to know that PottyMouth is being used.
WikklyText is a Python-based wiki and modular library for creating custom wikitext rendering applications. Its wikitext engine is compatible with the TiddlyWiki markup language. It functions equally well as a wiki-on-a-stick or as a multiuser wiki behind Apache. It includes a Drupal plugin as well.
itools is a collection of Python libraries which provides a wide range of capabilities, including an abstraction over directory and file resources, a search engine, type marshallers, datatype schemas, i18n support, URI handlers, a Web programming interface, a workflow interface, and support for data formats such as (X)HTML, XML, iCalendar, RSS 2.0, and XLIFF.
xmlrpcserver is a simple to use but fairly complete XML-RPC server module for Python, implemented on top of the standard module xmlrpclib. This module may, for example, be used in CGIs, inside application servers or within an application, or even standalone as an HTTP server waiting for XML-RPC requests. xmlrpcserver is completely written in Python and has no dependencies other than standard modules.
Myghty is a Python-based Web application framework originally ported from HTML::Mason. It supports the full feature set of Mason, allowing component-based Web development with Python-embedded HTML. It also features additional paradigms such as module components, environment-neutral session support, and many more language features. The HTTP connector API includes mod_python, CGI, WSGI, and standalone implementations. It also supports command line and custom non-HTTP environments.