The main items you will need are the coins, I used the coins of my country. Any size would be good, but the bigger the better. Cardboard is also important in this project, almost everything is made using 3mm cardboard. For the sound I used an old 128mb MP3 player. A servo hacked for continuous rotation. If you buy a new servo, it will probably come with a few handles, I you use a old servo you will have to make your own handle. Two springs, one to push the coins up, and another to push the coins into the charger. A small piece of a thin plastic, like the kind used in credit cards. Electronic stuff is detailed in step 10.
Step 2: How does it work
First we have a stack of coins in a tube. A spring pushes them forward. Then a plastic lever grabs them one by one. The servo moves the lever down. And releases it making it push the coin up. It is controlled by a timer (based on a 555) that fires with each hit to the block. The timer must be configured to make the cursor of the servo turn 360 degrees. Also parallel to the timer button is the play button. So you will hear the sound of the coin every time you press it.
Step 3: Prepare the mp3 player
Easy step, open your mp3 player and find the play button, solder two wires to it and then solder a switch to this wires, in order to make an extension of the play button.
You have to make an empty folder with just the sound of the coin, so each time you press the button you heard the sound of the coin.