Windows convenience

• Daemon Tools – Mount CD/DVD images
• XFree86 monospace fonts for Windows
• Pidgin
• Safari

Typesetting and presentation

• MiKTeX – TeX for Windows
• WinEdt – Convenient LaTeX editor for Windows
• DjVu Viewers/Plugins

Design

• GIMP – Image manipulation (open source)
• Inkscape – Scaleable vector graphics (open source)
• Blender – 3D design, cartoons, animation, photo-realism (open source)

Windows programming

• Windows Sysinternals
• P/Invoke Templates – .NET templates for invoking legacy Windows DLL functions
• X-like mouse for Windows
• TortoiseCVS for Windows
• TortoiseSVN for Windows

Java programming

• General Large Java Project Tools
• IntelliJ – Most popular in industry Java IDE
• prefuse – Interactive visualization toolkit

Programming language design tools

• eXTensible C – Source-to-source transformator
• Jekyll – A mix of C, Haskell, Modula and others
• Cyclone – A safe dialect of C

C++/Python/etc.

• SWIG – Cross-language interface tools
• Perforce – Powerful commercial versioning system
• SCons – A replacement for automake/autoconfig

JavaScript, HTML, HTTP, FireFox Add-ons

• Scriptaculous – user interface in JavaScript
• FireBug – (FireFox add-on) Essential for debugging JavaScript apps
• Aardvark – (FireFox add-on) Interactive DOM inspection
• Live HTTP Headers – (FireFox add-on)

Flash, Flex, ActionScript

• SwfMill – XML to/from SWF processor
• MTASC – Motion-Twin Actionscript 2 Compiler

Sheer pleasure

• FoxClocks – (FireFox add-on) International times
• rein – (FireFox theme) Clean and pure

Hardware

• Adesso — Ergonomic and unusual keyboards and mice