Sure, there's plenty of puzzles and challenges over at the Mental Gym, but for those who seek further brain-straining, even more await out on the web!

I'll start with the more familiar puzzles. If you'll fire up your computer's or browser's Java Virtual Machine, we can head over to MazeWorks. This site features many classic puzzles, such as the 15-puzzle and the Towers of Hanoi, along with many new puzzles you may enjoy discovering.

Let us not forget the humble logic puzzle. How about starting by trying to get our hero a kiss from a pretty girl? If that's not enough, and you can keep from peeking at the answers, here's 13 more puzzles for you to solve!

If you're a fan of Sudoku, you can head over to the Mental Gym's Sudoku page. However, if you wish to delve deeper into the nature of the game, see what happens when sudoku and mathematics intersect.

Understanding the principles behind the puzzles may or may not help you solve them, but it will help you understand the nature of the puzzle itself. This can even help you create new puzzles. As a matter of fact, Maki Kaji, the father of Sudoku, has used similar principles to create a new type of puzzle called Masyu (PDF, will open in new window). If you want to try this Masyu puzzle for starters (PDF, will open in new window). Don't worry, there are already plenty of Masyu puzzles available on the web if you get hooked.

Oh, and if you need any help solving any of these puzzles, take some advice from Square One TV's Larry Cedar: