Ask HN: Good examples of fault-tolerant Erlang code?

Hi HN! I'm trying to learn more about Erlang and how it achieves fault-tolerance. I am pretty up-to-date on the talks that Joe Armstrong gave, and I've read his thesis. This is already quite informative, but I wonder if there are any codebases out there which are good examples of fault-tolerance.

I'm particularly curious about when to split off a new process, and what "if things fail, do something simpler" means in practice.

Any suggestions?