Jellybean is a Perl Object server that allows people to write custom applications following a simple interface and framework. It's conceptually similar to Zope, but has peer communication potential. It has its own tiny Web server which serves static pages, CGIs, or transforms URIs into method calls on objects, and allows users to create their own behavior.
Load is a utility for Web application and SOAP-based Web services performance and scalability testing. It features a scripting language and a library of test objects for the creation of intelligent agents that drive the Web application or SOAP-based Web service. Running hundreds of agents concurrently shows how your software performs in production environments. Load is a Java application that runs on Linux, Solaris, NT, Win2000, and Macintosh. While Load continues to be maintained, the next generation is the TestMaker program.
Twisted is an event-based framework for Internet applications. It includes a Web server, an SMTP/POP3 server, a telnet server, an SSH server, an IRC server, a DNS server, a generic client/server pair for remote object access (Perspective Broker), and APIs for creating new protocols. It supports integration with GTK+, GTK+ 2, Qt, Tkinter, wxPython, Mac OS X (PyObjC) and Win32 event loops. It also supports TCP, SSL and TLS, UDP, Unix sockets, multicast, and serial ports. Supported protocols include HTTP, FTP, SMTP, POP3, IMAP, TOC, OSCAR (AIM and ICQ), SSH, DNS, IRC, NNTP, Jabber, SOCKSv4, Telnet, SIP (for VoIP), and XML-RPC and SOAP using external packages. Most protocols are supported as both servers and clients.
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.