Perfect Circle - Test your designer skills!
DecodeChess - AI chess tutor and analysis
Chesscademy - A fun and free way to learn chess.
ChessDB - ChessDB - a free Chess database for Mac OS X, Windows, Linux, and UNIX - like ChessBase, but better
Halfchess - Learn to be a better Chess player, playable in your browser
ChessPad - ChessPad is a feature-rich chess game viewer and PGN file editor available for Windows.