Classz is a simple, yet user-friendly drag-and-drop GUI shell around the venerable "class-dump" command-line utility by Steve Nygard. Classz incorporates an unmodified binary of class-dump 3.1 as distributed by Steve Nygard.
Classz is primarily a developer's tool, but may appeal to the terminlly curious non-developer. You can drop any OS X Cocoa application/library/whatever onto Classz and it will create and display interface files for the Objective-C code that created the application.
REQUIREMENTS: Mac OS 10.4 or later
To download a trial copy of Classz (1.0MB), click here.
Links:
[1] http://dl.maclife.com/classz.dmg
[2] http://thinkertons.com