I know this plugin has existed for a while, but I just recently noticed it was featured on the MT plugin website. For all of you bloggers looking to start podcasting who use Movable Type, this plugin is what you have been looking for.
“Brandon Fuller’s Enclosures plugin brings podcasting power to Movable Type. Podcasting is one of the fastest-growing new uses for blogs these days, allowing blog publishers to distribute MP3s and more directly to your audience’s iPods, laptops, or other mobile devices.”