Ghostscript, Ghostview and GSview

Ghostscript is an interpreter for the PostScript (TM) language. A PostScript interpreter usually takes as input a set of graphics commands. The output is usually a page bitmap which is then sent to an output device such as a printer or display. PostScript is embedded in many printers.

Ghostscript has several main uses:

1. Display a PostScript file (avoid killing trees).
2. Display a PostScript file to decide if you really need to print it (reduce the number of trees killed).
3. Print a PostScript file to a non-PostScript printer (kill more trees).

An example of a very simple PostScript file is:

%!
/Helvetica findfont 72 scalefont setfont
72 72 moveto
(Hello, world!) show
showpage

The first line is a PostScript comment. It is ignored by the PostScript interpreter, but enables other programs to recognise that the file contains PostScript commands. The second line says to find the Helvetica font, scale it to 72 points high (1 inch) and then set it as the current font. The third line moves the current point to 1 inch in from the left and bottom edges of the page. The fourth line draws the text into the page bitmap at the current point. The final line causes the page bitmap to be output to paper or the display.

The information below assumes the use of Windows 95 or NT, but Windows 3.1, OS/2 and Unix are similar.

http://pages.cs.wisc.edu/~ghost/

Vista/XP Virtual Desktop Manager

One of Vista's most talked-about new features is the Desktop Window Manager (DWM). A new set of thumbnail API's can be used to access thumbnails of open windows. This virtual desktop program takes advantage of this new API and uses some tricks of its own to provide a powerful virtual desktop manager with a full screen thumbnail based preview. You can have as many desktops as you want and can seamlessly switch between them.

http://www.codeplex.com/vdm

But wait! What if you still are using XP? Don't worry, Vista/XP Virtual Desktops provides support for XP as well, although window previews are not live since XP doesn't have DWM.