Best of The Rest

132 Studies and Problems - a large collection of problems composed by J.T. Sanderse

Archive of chess problems - in French

Archives des problémistes - In French.

Beautiful Chess Studies - currently around 16 problems

Chess Composition - fairychess, endgame, and other compositions

Chess Composition Books - electronic editions of public domain chess composition works.

Chess Online Problems - A multitude of Problems.

ChessPlanet Problemschach

Chess Problem Archives - a site specializing in chess problems including original and archived material. Mostly in French

Chess Problems From Around The World

Chess problems of 1001 years ago - from the Chess variant pages

Chess Problem Page

Chess Problem Server - A selection of practical problems..

Chess Problems Unlimited - endgame, mating, and combination problems

Chesspro's Chess World - by Ramon Merel, a correspondence chess master

Chess Tactics Center - a place to test and sharpen your tactical chess skill

CHEST

Classic Chess Problems - a modest collection

Combinations in the Chess Game - regularly updated with new combination tactics tests from actual chess games

Don French's Chess Problem Page - includes a number of his own compositions

Endgame Of The Day - here you can view a new endgame daily or have it sent to you via email

Exeter Chess Club: Studies and problems

Fun Chess Positions - positions from a book published by John Coffey

Glanz auf 64 Feldern - mostly German

GorFo Chess Problems

Harmonie's home page - a chess problem magazine published by Frank Richter

Les échecs - Studies, problems and games online using javascript.  Pages are in French.

Library Catalogue of the British Chess Problem Society - looks to be a large collection to download

Juraj Lörinc's Chess Composition Microweb - contains problems (mainly fairy chess), tournament announcements, awards, and discussion on various topics

Key Moves - nice site where you can test your tactical eye

Manolis Stratakis Chess Problems Page

Mario Velucchi's Personal Interests

Mat Plus - The Best of Chess Problems - terrific site with a large number of chess problems and problem contests

Peter Schaefer's Problem Chess Page - a German page including fairy chess problems, retroanalysis, articles, and links

Popeye - a program to solve fairy chess problems

Practical Chess Ending + Computer Analysis - A new ending to solve each week. Computer analysis also considered.

Problemesis - Webzine devoted to chess problems.  The site is in both English and French.

Problemiste - Chess Problem software.

Problem Chess in Upper Austria (Problemkunst in Oberösterreich) - Chess problems and biographies of 4 upper austrian chess problem artists.  The page is mostly in German with some english annotations.

Retractor -   allows one to set up a position and play backwards from it, checks for common illegalities to rule out many illegal moves.  Useful in retrogade analysis.

Stockholm Chess Association - has an Internet Problem-Solving Tournament

Solving Contest for Mathematical Chess Problems 1993 - a number of helpmate problems

Stanislav Vokal's Chess Compositions - huge collection

Torsten Linß' problem chess page

Unknown Programmers Chess Page - a small collection of interesting chess problems

Vincent's Chess Problems Page - over 100 problems

Vito Rallo's Home Page - in Italian and English

Bruno's Chess Problem of the Day -  In English and French .A different problem everyday! Levels of difficulties are available ranging from very easy (checkmate in 1) to very difficult (checkmate in 6 or more). Solution to the problem is made available the next day. Archives of problems over the last 10 days can be consulted.