Not all audio media is created equal, but we seem to all consume it in the same way. In an effort to create unique interfaces for the unique audio we interact with (some of us, myself included, on a daily basis), I created a series of interfaces showing how different types of audio can be consumed differently.
In this example, I introduce the notion of bookmarking podcasts. Since audio-listening interfaces, like the one at the top of the iTunes app, or that displays on the lock screen of an Android, are typically designed for music, there has never been a need for a bookmarking function. Unless one is a professional musician or producer scouring for ideas for a new tracks, it's unlikely that a user will be listening to a song and want to mark a particular section that made an impression.
Podcasts are different. It's not uncommon to want to share a snippet of a podcast with someone--a part of an interview that resonated, a funny joke or bit that you know a friend would like, a fact that you'd like to cite in your own work or research. But scrubbing through hours of podcasts trying to find a few seconds that you liked is irritating. Unlike video, there are no visual cues to remind you of what was happening when in a given episode.
The bookmarking function in this audio interface serves as something like the highlighting function you would see in an e-reader. The user selects the start of the audio they would like to remember. If they want to want to share that section with someone else, they can tap and hold--a sharing widget will appear.