This may not work with all calculators. Here is an interesting way to count footsteps and estimate how far you have walked.You need a cheap calculator, some foam or sponge, glue, foil, cellophane tape, and 2 long wires.
Open up the calculator and connect each of the other wire ends to the top and bottom contacts of the "equals" aka = button. Put a piece of cellophane tape between the contract so that they do not connect. Close the calculator and make sure everything works normally. you would have to press the switch together for the = sign to work. Attach the switch to the bottom of the shoe.
Now enter "1 + 1" into the calculator. Start waking and you will see the count begin to rise as you walk. When you are finished walking multiply the steps to the length of your stride and you will have your distanced walked.