It's an SEO's duty to try to utilise and leverage as many opportunities as possible for clients and employers in order to drive relevant traffic to their websites.
Transcriptions that can become content...
- Presentations, panels, keynotes
- Vox pops between sessions
- PR stunts (if they're filmed)
- TV & Radio
Full TV/radio shows
- Appearances on TV/radio shows (e.g. if your client only appears on a five-minute segment)
- Appearances on podcasts
Lyrics (especially if it's an unsigned band)
- Live shows (especially if there's banter between songs and/or alternative lyrics)
- Whiteboard videos
- Corporate/promotional videos
- Testimonial videos (as in testimonials from clients/customers)
- Google+ Hangouts
- Videos with commentary/voice-overs
- Pretty much everything/anything that has (or could have) audio!
Comment: I would never have thought of using some of these as content, but of course they are helpful in adding keyword rich text to websites and other media.