MATHguide has a special brainteaser section and links to puzzles.

    Scroll down to the name of the problem you wish to view, then click on the 'Go' button.

Problem Name: Against The Wind Arcs and Chords and Segments, Oh My! Circular Logic Congruent Circles Eat Crow Fair Trade The Farmer's Eggs Funky Factors The More, The Merrier Shake On It Siblings Stubborn Solution Time Warp The Two Towers We Are Family

• Bradley University's Problem of the Week
• Swarthmore's Problem-of-the-Week
  
  
• Gamedesign's Index: Kaeru Jump and Sudoku.
• Triple Quintzee - Last Homely House
• Hex 7 - MazeWorks
• Reversi - Passagen
• Dots - The Well
• Chess: Sourceforge, Lokasoft, and Pathguy.
  
  
• Puzzle Contests