PCMan X aimed to be an easy-to-use yet full-featured telnet client facilitating BBS browsing.

PuTTY is a free implementation of Telnet and SSH for Win32 and Unix platforms, along with an xterm terminal emulator.

Tera Term (Pro) is a free software terminal emulator (communication program) for MS-Windows. It supports VT100 emulation, telnet connection, serial port connection, and so on.

WeirdX is an X Window System server in pure Java under GNU GPL.
It is derived from WiredX-Lite and will run on any platforms which support Java 1.1. This X server will not be suitable to exec heavy x clients, but you may find that twm, xterm, etc. will run fine on it.

RealVNC provides remote control software which lets you see and interact with desktop applications across the network. The software has a widespread user base from individuals to the largest multi-national companies. The company was founded by the original developers of VNC to promote, enhance and commercialize VNC.

TightVNC is a free remote control software package derived from the popular VNC software. With TightVNC, you can see the desktop of a remote machine and control it with your local mouse and keyboard, just like you would do it sitting in the front of that computer.

UltraVNC allows you to remotely access your computer from any Internet-connected computer in the world.

EchoVNC is a secure, "firewall-friendly" remote-desktop tool based on Ultr@VNC with echoWare integration. With it, a Windows PC can be remotely accessed regardless of firewall, router or web-proxy configuration

BO2K is the most powerful network administration tool available for the Microsoft environment, bar none.
Built upon the phenomenal success of Back Orifice released in August 98, BO2K puts network administrators solidly back in control. In control of the system, network, registry, passwords, file system, and processes. BO2K is a lot like other other major file-synchronization and remote control packages that are on the market as commercial products. Except that BO2K is smaller, faster, free, and very, very extensible. With the help of the open-source development community, BO2K will grow even more powerful. With new plugins and features being added all the time, BO2K is an obvious choice for the productive network administrator.

With synergy, all the computers on your desktop form a single virtual screen. You use the mouse and keyboard of only one of the computers while you use all of the monitors on all of the computers. You tell synergy how many screens you have and their positions relative to one another. Synergy then detects when the mouse moves off the edge of a screen and jumps it instantly to the neighboring screen. The keyboard works normally on each screen; input goes to whichever screen has the cursor.