curl and libcurl is a tool for transferring files using URL syntax. It supports HTTP, HTTPS, FTP, FTPS, SCP, SFTP, TFTP, DICT, TELNET, LDAP, POP3, IMAP, SMTP, RTSP, RTMP, and FILE, as well as HTTP-post, HTTP-put, cookies, FTP upload, resumed transfers, passwords, port numbers, SSL certificates, Kerberos, and proxies. It is powered by libcurl, the client-side URL transfer library. There are bindings to libcurl for about 40 languages and environments.
Dosage is designed to keep a local copy of specific Web comics and other picture-based content such as Picture of the Day sites. With the dosage command line, script you can get the latest strip of a Web comic, catch up to the last strip downloaded, or download a strip for a particular date/index (if the comic's site layout makes this possible).
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.
Submin provides a Web-based admin interface to your Subversion and Git repositories. Its features include user/group management, path permission management, the ability to create svn repositories and managing commit email messages. For Subversion, authentication is done with htpasswd/svn authz, so it can use the same login information as apache2/svn (and trac). For Git, ssh is used, and the login information is synched whenever a change is made. The Web interface can also work with NGINX/uWSGI, but the Subversion part only works with Apache.