Snood is a puzzle game that is almost, but not quite, entirely unlike Tetris.
Snoodoku is a puzzle game that is almost, but not quite, entirely unlike Minesweeper.
I've been playing the former for at least a decade and have a win rate on the "evil" setting of around 70%. The latter I downloaded a few days ago, much to the detriment of every other hobby presently in my life. There are a bunch more games by the same guy at Word of Mouse Games, but I think I'm set for another decade.