I've discovered some variations on newer jigsaw puzzles. There are perpetual puzzles-from
lagoon puzzles in the UK. and jigfinity from the same company.
A couple of mentions in the games category that remind me of puzzle strategy: Burley Games from germany (from peter Burley) has the solo player game:Take it easy. "Six" is an abstract strategy game of shapes and placement for either 2 or 4 players.