External viewer

Universal Viewer (ATViewer) is an advanced file viewer with wide range of formats supported.

You can define ATViewer as external viewer in FreeCommander:

If you have defined the viewer, simply push Shift+F3 for opening the ATViewer.

Details and download.

Editor

PSPad is an universal freeware editor. You can define PSPad as external editor in FreeCommander:

If you have defined the editor, simply push F4 for opening the PSPad program for the selected file.

Details and download.

Compare files

WinMerge is a open source tool for visual difference display and merging, for both files and directories.

You can define WinMerge in FreeCommander as a program to compare text files.

If you have defined the program in FreeCommander, you can select two text files and then start the compare files with Ctrl+Alt+V.  The two text files can be selected in one window or separated in two windows.

Details and download.

Another freeware tool is AptDiff. AptDiff enables you to visually compare text and binary files. You can define AptDiff in FreeCommander:

C:\Program Files\AptDiff\aptdiff.exe /text /f1 %FileCompare1% /f2 %FileCompare2%

Details and download.

Other tools and links

Free Windows XP and Vista tools http://www.thoosje.com