AudioBlog
Some would call it a podcast, and whilst technically the same, I think a podcast implies a produced piece of audio; mine isn't produced at all, it's just my random thoughts on stuff, much the same this Weblog. With my iRiver IFP890 (purchased of ebay especially for the task) I can record stuff in the car and just upload it when I get in. In fact, this small post has already taken longer than it takes to stick my AudioBlog up.
So, if you want to listen, you can subscribe at http://feeds.feedburner.com/pwdmarshall - stick it in your PodCatcher (iTunes, Juice, etc) and enjoy (or not, as the case may be). If you're not familiar with subscribing to podcasts, leave a comment and I'll let you know.