drawAblank software: PuzzleGetter Utility to download crossword puzzles from various newspapers in AcrossLite format. (for Mac OS X)
The New York Times Crosswords & Games The daily crossword puzzle with four ways to play, plus free classic crosswords and trivia quizzes. Subscription required.
CrosswordLinks.com A comprehensive resource with rules and helpful tips, articles, software, forums, and information about leagues, tournaments and online play.
Xwords.co.uk Play online or print and solve. Also offers creation tool. Registration is free.
XWord - Crossword Compilers A collection of various styles of puzzles by Anina Roux and her team, compiled for magazines and newspapers in South Africa.