Many more items will be added to this list, currently if you Google examples of Content Types tend to be a bit abstract:
- Memorandums
- Military Operations
- Reports such as the Mueller Report!
So any Report could (generally) be represented by a Content Type ~
a reusable set of metadata
And importantly a specific Word Template can be associated with such Content Types!
The 'Mueller Report' would be significant enough to have it's own Content Type as it would have gone through many releases (as well as versions).
Of course this gives rise to the use of Content Type Syndication to 'standardise' Content Types across farms.
To give some common examples that are thrown around
- Meeting Agendas
- Meeting Minutes
can be pretty straightforward e.g. a couple of bullet points or a text file - depends on how much control an organisation wants to exert on this particular set of metadata etc ...