I just learned about iSpring Free, a free PowerPoint to Flash Converter from the Connecticut Discovery Educator Network. It is easy to use and free. What a great way to share PowerPoint presentations on the web or in other applications. (once again, my PLN comes through with great resources).
It is a free download from the site. Install the software, open your PowerPoint presentation, click Quick Publish, and you will get a .swf file from your presentation. It will install a toolbar in PowerPoint. The toolbar has the Quick Publish button, as well as the ability to insert Flash and YouTube videos into your presentation.
I converted a 162 slide PowerPoint presentation (32 MB) to flash in 5 minutes. Not bad at all.
Very easy to use, quick, and FREE.