Adventure Puzzles - Serial adventures, continuing story and puzzles building towards a final puzzle and solution.
Crosskit.com - Offers printable crossword and sudoku puzzles. Puzzles are offered daily and weekly with an archive. Also offers a crossword dictionary, daily horoscope, and discussion forums.
The Game - A puzzle hunt run every year at Stanford.
Holiday Puzzles - Collection of original puzzles developed over the years to celebrate the winter holidays.
Logicville - Educational puzzles, brain teasers, mathematical recreations and word games. A resource for anagrams, cryptograms, alphametics, word puzzles, logic problems, doublets, tangrams, chess, and math quizzes.
MyCharades.com - Includes charades, riddles, and enigmas.
The Puppeteer's Cosmic Puzzle - Pictographic puzzle microcosm of old and new playing cards, poems, games and lore. New suits: the zodiac, solar system, evolution, human family, ancient elements, astronomical basis of the calendar and compass.
Puzzle Choice - Crosswords, wordsearches, cryptograms, quizzes, wordplay and other interactive and printable puzzles and games.
Puzzle Monster - Original trivia, logic, visual and word puzzles.
The Puzzle Page - Collection of puzzles, brain teasers, mind benders, logic problems, cryptograms, patterns, and enigmas.
Puzzle Space - Information about language and culture independent puzzles and logic games.
Puzzletome - Contests of varying difficulty and types. Also has tutorials with worked examples and practice games. [Registration required]
Rainier Beer Bottlecap Puzzles - The answers to the bottlecap rebus style puzzles found on Rainier Beer and Pearl Beer caps.