>The $600 Flash authoring tool is the only way to produce Flash applications. That statement is wrong. Anyone can create tools that can 'create' and/or 'run' swf files. Adobe itself provides Flex SDK cost free. It is an opensourced framework. http://osflash.org/projects has a list of opensource tools available to create flash content.
I'm curious, please provide link to any capable tool.
Scribd uses 'pdf2swf' from swftools.org to convert pdfs(Not sure if they still use it. ref: http://www.swftools.org/references.html )
Scaleform depends heavily on Flash[scaleform.com]. Ming library is a nice option to create dynamic swf files on server side[libming.org].
A nice little online editor and compiler can be found here: http://www.victordramba.com/?p=31
Although there are so many nice, robust open source tools built around Flash, i haven't heard of Adobe actively promoting any of them.