I should also have mentioned some of the enormous repositories of interactive fiction:

The Interactive Fiction Archive
http://www.ifarchive.org/

The Interactive Fiction Database - IF and Text Adventures
http://ifdb.tads.org/

The People's Republic of Interactive Fiction - Play
http://pr-if.org/play/

Baf's Guide to the Interactive Fiction Archive (a great resource, but died in 2013)
http://wurb.com/if/
Luckily the Internet Archive has kept a copy:
https://web.archive.org/web/20130112231747/http://wurb.com/if/index


And I completely forgot about the lower profile Spring Thing competition:
https://www.springthing.net/2020/
I have a funny feeling it may be based in Australia... though I could be wrong about that.