There are several online puzzle competitons catering to reasonably advanced puzzle solvers. None have prizes.

For example,

PQRST - run by Cihan Altay

Forsmarts - run by Vladimir Portugalov

IPST (Internet Puzzle Solvers Test) - run by the Russian puzzle club Diogen

WPC (World Puzzle Championship) - run by the World Puzzle Federation

PDT (Puzzle Design Tournament) - run by Cihan Altay

Turkzeka - run by Yilmaz Ekici

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