You already know that Mathematica can do anything technical—modeling, simulation, development, documentation, and so on.

But it’s also a great tool for relaxing. When you need to take a break from your engineering project or math homework, you don’t have to shut down Mathematica. Clear your head with one of these fun activities created by Mathematica users for the Wolfram Demonstrations Project.

Solve a Crossword Puzzle

If you’re like me, you hate to leave a crossword puzzle unfinished. But there’s always that one pesky clue I just can’t get. The Crossword Helper Demonstration lets you plug in the letters you already know and the number of blank letters you still need, so you get a list of words that fit.

Play Sudoku

Based on one of the most popular puzzles in the world, the Sudoku Game Demonstration lets you rack your brain (in a good way!) trying to solve one of these number puzzles in Mathematica. You can even make the puzzle harder or easier, depending upon your skill level.

Find the Disappearing Square

Here’s a brain teaser to occupy your mind for a while. See those five red squares in the middle? Use the slider to adjust the puzzle. Five squares turn to four. Where did the other one go?

24

Take any four numbers. Now use your math skills to create an equation that adds up (or subtracts or divides or…) to 24. Definitely a fun way to test your abilities. And if you get stuck, just plug the numbers into the Krypto, or 24-Game Demonstration for a little help.

Measure the Speed of Light with Marshmallows

Sounds a bit farfetched, eh? It’s all a simple matter of physics. All you need is a microwave oven with no turntable, a ruler, and a handful of yummy marshmallows. But try not to eat any until your experiment is complete.

Find Your Town’s Namesakes

If geography is your hobby, you’ll love Mathematica‘s built-in city and country data and its many interesting facts, some shown in the Your Town’s Namesake Demonstration. For instance, I was born in Monticello, Illinois (population 5,275!). But how many other Monticellos are there around the world? Mathematica tells me instantly that fifteen other towns named Monticello exist in the United States… and there’s one more in France to boot!

Play Music

Who needs a piano to play Chopin? Whether you’re into classical, ragtime, or Billy Joel, clicking your mouse turns you into a master pianist with the Piano Keys Demonstration. This Demonstration is great for teaching music too, because the notes can be printed right on the keys.

What’s your favorite leisure activity with the Wolfram Demonstrations Project or Mathematica? Let us know in the comments below.