NetCrawler is the frontend to a Web crawling system. This command line application will download all of the pages within a domain, and then parse and process all of the relative content (Images, Text, Audio, Video), saving this content within an XML document for later processing. It is definitely alpha quality, but has been used quite extensively.
pyOpenSSL is a Python wrapper for a subset of OpenSSL's functionality, featuring an advanced error management system, connection objects that wrap socket methods, and flexible context objects. Also included is a rudimentary crypto module that can be used to create and verify certificates (X509 objects).
Medusa provides a framework for implementing asynchronous socket-based servers for TCP/IP, and on Unix, Unix domain sockets. The first release includes HTTP, FTP, and 'monitor' (remote python interpreter) servers. Medusa can simultaneously support several instances of either the same or different server types - for example you could start up two HTTP servers, an FTP server, and a monitor server. Then you could connect to the monitor server to control and manipulate medusa while it is running.
Tkinter is Python's de facto standard GUI (Graphical User Interface) package. It is a thin object-oriented layer on top of Tcl/Tk. To use Tkinter, you don't need to write Tcl code, but you will need to consult the Tk documentation and occasionally the Tcl documentation (since Tk's low-level event handling mechanism is considered part of Tcl).