0. Paper and pencil; whiteboard/blackboard and post-its

1. Drafting and mockup tools:
    • Wireframing software (Balsamiq, Mockingbird, Omnigraffle, Hotgloo)
    • Presentation software (MS Powerpoint, Apple Keynote)
    • Hypermedia authoring tools (Adobe Director, Adobe Flash; ToolBook,...)

2. "GUI builders" (Visual Basic/C++/J#, Borland JBuilder,...)

3. WYSIWYG web authoring tools (Dreamweaver, KompoZer)

4. GUI toolkits (Windows/Macintosh/Unix X toolkits, OSF Motif, ILOG Views...)

5. Application frameworks with UI classes, objects methods (MFC, Cocoa)

6. Scripting languages (Tcl/Tk)

7. Application-specific GUI builders (MS Access)

 
8. Critiquing Tools (e.g., CogTool, accessibility validation )

 
Consider time to learn, time to build, ease of integration, extensibility, runtime efficiency