Develop Articles on Testing and Debugging
Several good articles on Mac OS debugging, including "Macintosh Debugging: A Weird Journey into the Belly of the Beast", "Macintosh Debugging:The Belly of the Best Revisited", "Balance of Power: MacsBug for PowerPC", "Sleuthing Through Your Code" and "Balance of Power: Stalking the Wild Defect".
http://developer.apple.com/dev/techsupport/develop/bysubject/testing_debugging.html

Debugging JavaScript programs
Everyone makes mistakes writing JavaScript programs. Errors don't know experts from novices, so the next time you get an error message while trying to play a JavaScript program you've written, don't feel bad. JavaScript provides error messages as a means to help you spot mistakes. This column describes the errors you are likely to get when writing a JavaScript program and what to do about them.
http://www.javaworld.com/javaworld/jw-07-1996/jw-07-javascript.html

Team Remote ASP Debugger
SplineTech JavaScript Debugger, Team Remote ASP Debugger, SplineTech VBS Debugger. Debug JavaScript, debug ASP, debug VBS.
http://www.aspdebugger.com/

ASP Debugger
SplineTech JavaScript Debugger, Team Remote ASP Debugger, SplineTech VBS Debugger. Debug JavaScript, debug ASP, debug VBS.
http://www.remotedebugger.com/team_remote_asp_debugger.asp

Dedicated Debugging Tool (DDT)
A full screen debugging tool, DDT captures the interrupt vectors and allows users to debug and alter the execution environment in a number of ways.
http://webhome.idirect.com/~aeinc/ddt/Ddtdoc.html

Omniscient Debugging
An experimental debugging tool written in Java which allows "rewinding" and seeing what the values of variables were in the past. Works by modifying bytecode. [Freeware]
http://www.lambdacs.com/debugger/debugger.html

Microsoft Debugging Tools
Provides links and information about tools, downloads, and recommended techniques for debugging drivers for Windows operating systems.
http://www.microsoft.com/whdc/devtools/debugging/

SannySoft
SannySoft Perl Editor is a fully integrated developer environment for Perl programmer
http://www.sannysoft.com/

Script Debugger IDE
A development platform for building custom business solutions. It includes a powerful script and form editors and debugging tools for Microsoft VBScript and JScript. It supports full client and server script debugging.
http://www.script-debugger.com/products/scrdebugger/

Libcwd
A thread-safe library to support C++ developers with debugging their applications. It includes support for ostream-based debug output to custom debug channels, memory allocation debugging and run-time support like printing source file locations and demangled names of template parameters.
http://libcwd.sourceforge.net/