List/Search all existing UTIs (Uniform Type Identifiers)

How about

 /System/Library/Frameworks/CoreServices.framework/Frameworks/LaunchServices.framework/Versions/A/Support/lsregister -dump

Even better: A Graph of all Universal Type Identifiers - Kevin Ballard's Blog

You can build your own graph with UTIsExplorer https://github.com/nst/UTIsExplorer

The project includes a graph of all UTIs on my machine: http://seriot.ch/resources/utis_graph/utis_graph.pdf