Add another item to the list of things you should try in your email newsletter.  B-to-B Online says you should deliver podcasts to your email newsletter audience. If you're not up to spinning up your own show, you can always advertise on existing podcasts, which can be an easier but worthwhile path according to Hubbard Chicago in their piece, Why Podcasts are an Effective Marketing Tool. If you don't know what podcasting is: Catch up at wikipedia.

Enjoy