Here is a demo of a  slidecast a created in about 15 minutes. The goal was to find an easy way to combine sound and still images without having to learn a video editing tool.

1. I started by adding a series of photos to a PowerPoint presentation.
2. I went through the presentation while recording a voice narrative into my iPhone (this would also work if I were recording a lecture).
3. I brought the .m4a file audio file into Audacity and made some basic edits, normalized the track volume and exported as a .mp3 file (optional step but well worth the effort)
4. Finally, I uploaded both the .ppt and .mp3 files to Slideshare.net and timed the audio to the slides using their built-in tool (really easy). Below is the embedded slidecast:

Wildflowers