Gow (GNU On Windows) is a lightweight alternative to Cygwin. It uses a convenient Windows installer that installs about 130 extremely useful open source Unix applications compiled as native Win32 binaries. It is designed to be as small as possible, about 10 MB, as opposed to Cygwin which can run well over 100 MB depending upon options.
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).
AutoRPM is a program that can do any combination of the following: mirror RPMs from an FTP site, keep installed RPMs consistent with an FTP site or local directory and keep installed RPMs in a cluster or network of systems consistent. It is highly flexible and contains a fully command-line driven interactive install mode (for installing RPMs from the queue or for installing RPMs from your system interactively). It also handles recursive dependencies, multiple versions of the same RPM, the same RPM with multiple architectures, and more. It does some of the same tasks as up2date and AutoUpdate.
X11, or X, is a vendor-neutral, system-architecture neutral network-transparent window system and user interface standard. In other words, it's a GUI for UNIX. X can use your network -- you may run CPU-intensive programs on high powered workstations and display the user interface (the windows) on inexpensive desktop machines.