A Game A Day: A puzzle site featuring a new puzzle format each weekday for each month. Puzzles are fun, educational, entertaining and are also printable.
A Puzzlemakers Site: Puzzles of all descriptions.
Able2Know: Message board of user submitted riddles and brain teasers.
Abnorm's Conundrums: Easy, medium and difficult brain teasers without answers.
All-Star Puzzles: Logic Problems: Collection of logic problems to solve. Printable.
Alphabet Cartoon Puzzles: Letters of the alphabet are used as structural components for drawings of figures and faces. Spelling tips lead to the solution of the puzzles.
Analytical Puzzles: List of logic puzzles grouped by difficulty.
Archimedes' Laboratory: Recreational mathematics including puzzles to make and solve, tessellations, geometric puzzles, optical illusions, and curiosities.
AVAV: Collection of optical illusions, brain teasers and riddles.
Bill's Brain Teasers: A collection of visual and linguistic riddles.
Brain Juice: An assortment of entertaining logic puzzles with solutions and indicated levels of difficulties.
Brain Teaser World: Offers riddles, puzzles, optical illusions, and magic tricks.
Brain Teasers: Brain teasers, riddles, logic puzzles and problems, paradoxes, optical illusions, IQ tests and logical games.
BrainBall: A daily brain puzzle with 10 different tasks and a variety of statistics on your performance.
BrainBashers: Brain teasers, puzzles, riddles, games and optical illusions.
BrainBoggled.com: A collection of math, logic, and word puzzles.
Braingle - Brain Teasers & Riddles: Contains a huge collection of user submitted and rated brain teasers and riddles. It also has a lively message board and some unique multiplayer games.
BrainVista: Collection of solved and unsolved brain teasers.
Confusion: Its a challenge to reach the end of this puzzle maze.
Curiouser.co.uk: Paradoxes, puzzles, games, optical illusions, poetry, curious facts, and quotations.
Eluzions: Featuring all sorts of games, optical illusions, puzzles, trivia, mazes, and magic tricks. Suitable for all ages.
Eye-Pleasing, Mind-Teasing 3-D Conundrums: Scans from a book of puzzles, includes English translations.
Eyetricks: Brain Teasers: Weekly puzzles and archives.
Game-Master's Page: Riddles, games, cryprograms, math puzzles, and forums.
Gray Watson's Brain Teasers and Riddles: A collection of brain teasers and riddles with a guess button.
Had To Play On: A community based site with competitions, challenges, awards, a help centre, forums and games.
iRIDDLER: Challenge your mind with free online riddles/puzzles, logic games, brain teasers and view optical illusions.
Just Riddles and More: Riddles, illusions, puzzles, and brain teasers.
Logic Puzzles Escapades: Logic puzzles with a satirical New Zealand tone.
National Puzzlers' League: Crosswords & other word puzzles and games, samples; monthly puzzle magazine; 800,000 word searchable list.
PedagoNet Brainers: Over 60 brain teasers to enhance your mind.
Planetarium: An on-line puzzle story in twelve weekly installments.
Professor Tangent: Have fun with games, puzzles, brainteasers and humor as you learn about logic and analysis.
Puzzability: Some real mind benders here.
Puzzle Contest Center: Riddles, brainteasers, cryptograms, anagrams, and logic puzzles. Compete in eight new contests monthly.
Puzzles Without Rules: Free, updated, original abstract puzzles for advanced puzzle-solvesr. Includes current unsolved puzzle and archive with hints and solutions.
Pzzls: A collection of logic puzzles, riddles and brain teasers.
Rec.puzzles Archive: An archive of many popular puzzles from the rec.puzzles newsgroup.
Roh'El's Riddles: Offers brainteasers rated by difficulty and category.
Say What You See!: Collection of visual brain teasers which can be solved by saying what you see.
Sesquip Word Games: Challenging word games published in newspapers.
Shashi's Homepage: Collection of puzzles, riddles and brain teasers.
The Amazing Art Site: Huge collection of optical illusions, hidden imagery, ambiguous art and upside downs.
The Grey Labyrinth: A beautifully illustrated collection of puzzles, riddles, and paradoxes. Features a changing "unsolved puzzle" plus three years worth of previous puzzles.
The Logic Zone: Collection of problems with answers, logic puzzles and cryptograms.
The Stone: an online mystery game. Hours of clever puzzles and riddles. Puzzles challenge the mind of serious and amateur players worldwide.
Thinking Game Forums: Chat and discussion about online thinking games.
Unitix Entertainment: Online games, puzzles and other interactive brainteasers. Fun for all ages.
Word Juxtapoz: Word puzzles, riddles, rebuses, brain teasers, mazes, cliparts and pictures.
Zuzzle Puzzles: Collection of puzzles including riddles, logic puzzles and sequential puzzles.