Nodes of mine that I like to reference:

• Running external commands
• File::Temp examples
• Return values of regular expressions
• /m and /s (includes visualization of regex matching)
• "open" Best Practices
• To glob or not to glob
• Building Regex Alternations Dynamically
• Truth and Falsehood (includes links to info on Perl's concept of Context)
• Parsing HTML/XML with Regular Expressions and Why a regex *really* isn't good enough for HTML and XML, even for "simple" tasks
• only perl can parse Perl (a few examples of simple static parsers)
• hash key autoquoting
• "alias"
• Threads about module versioning: Re: $VERSION in module files, Re: What basic things should I know about versioning modules?
• loading a module or an alternative (other conditional module loading threads: 1228945, 11109882, 1203288, 1165148, 1228300)
• Equivalencies of use ...
• MySQL+DBI SSCCE with Docker, Mojo::Pg SSCCE with Docker
• State machine pattern (an example)
• Re: Curious about Perl's strengths in 2018 (a list of "modern" modules)
• Debugging Unicode issues
• a Regexp::Grammars example along with multiple other approaches in the same node
• Posting binary data on PerlMonks (Windows hexdump: https://github.com/hollasch/hex)
• Links to threads about Unicode in Windows filenames
• Maximum values for integers
• How to Bisect Perl
• Fun with Prototypes and using prototypes to replace builtins
• various ways to do inplace editing (slurp/spew, File::Replace, etc.), equivalent of -i via $^I, slurping variants
• looks_like_number is (almost) the exact same function Perl uses for "not numeric" warnings
• Generate XML from Perl data structure (fairly generic)
• Various XML::Rules examples: bare minimum, simple, another, slightly more complex, with namespaces
• Data::Diver type code: here, here, here, here, here, here (see also Data::DPath, Data::Path, untested)
• Dump subs including closed over lexicals (and an attempt at dumping package variables used in subs)
• Tie::File adds significant overhead
• prompting examples
• various multiline string examples (for tests)
• how strict knows a variable was imported by tye
• alternatives to CGI.pm
• hippo's post on perl-core / RHEL: Re: Why not include version.pm
• My Mojolicious posts:
  • a Login example (see also RFC / Audit: Mojo Login Example)
  • Mojo::IOLoop based TCP server and client
  • a Mojo::SQLite query example and another simple example
  • Logging Serial Ports with Mojolicious (inlcudes Mojo::SQLite in-memory database and an EventSource example)
  • a simple example of Mojo::IOLoop::Subprocess
  • a more complex example of Mojo::IOLoop::Subprocess with progress via a EventSource
  • basic form submission
  • content negotiation
  • AJAX form submission (more of a jQuery example)
  • dynamic refresh of a page (more of a jQuery example)
  • a bit of redirects, routing, and tests
  • a request handler calling another HTTP API (getting the response asynchronously)
  • url_for vs. url_with
  • a WebSocket multiplexer
  • a comparison with old style CGI
  • Apache Pulsar WebSocket client
  • notes on Hypnotoad behind nginx
  • a hackish HTML editor
  • Mojo::DOM::Role::TreeWalker
  • Quite a few Mojo::DOM examples