Internet Logic Puzzle Competitions:

PQRST -- Puzzles Quarterly Rate Solve Ten

IPST -- Internet Puzzle Solvers Test

PDT -- Puzzle Design Tournament

For Smarts

Puzzle Laboratory -- graphic version. Ginormous collection of logic puzzles -- and it's still growing. You've got to be clever just to figure out the rules -- unless you speak Japanese.

Weekly Russian Crossword and Logic puzzle magazine. including several years archives. (Logic puzzles (including sudoku in recent issues) do not require knowledge of Russian to solve.)

Angela und Otto Janko

Fathom It Unlimited Battleship logic puzzles.