Comfort Keys Pro!

Free Virtual Keyboard is a free, lightweight, multilingual and finger friendly virtual keyboard.

On-Screen Keyboard is a utility that displays a virtual keyboard on the screen and allows users with mobility impairments to type data using a pointing device or joystick.

An ideal utility to be used to enter sensitive passwords. To avoid key loggers you can enter the password using only the mouse. This method protects you even against hardware keyloggers, or other keyloggers not supported by MyPlanetSoft Anti Keylogger. When the program is started, MOK deactivates all system-wide clipboard viewers, so you can safely copy passwords around different applications. Fully customizable keyboard. No installation required. Only ~70KB. For Microsoft Windows.

Neo's SafeKeys is an anti-keylogging virtual keyboard designed to counter keylogging, mouse-logging, clipboard-logging and screen-logging.

Hot Virtual Keyboard is a virtual keyboard software for Windows that lets type on a touchscreen, multi-touch screen or using any pointing device.

Kvkbd is a virtual keyboard for KDE, it contains many feature like system tray and dock support, autodetection and on the fly change of the keyboard layout, scripting with DBus, etc.

Extra Keys is a software input panel for typing international accented and other special characters.

Florence is an extensible scalable virtual keyboard for GNOME. You need it if you can't use a real hardware keyboard, for example because you are disabled, your keyboard is broken or because you use a tablet PC, but you must be able to use a pointing device (as a mouse, a trackball, a touchscreen or opengazer); If you can't use a pointing device, there is gok, which can be used with just simple switches.

KeyStrokes™ is an award-winning, fully-functional, advanced on-screen keyboard providing people with physical impairments as well as graphic tablet and touch screen users full access to the computer.