Manual counter with the keyboard or the mouse on images
The only open source counter to count any items the simplest and easiest way with the keyboard, or the mouse specifically on images. After associating a key to each item, or a predefined graphical symbol for images, pressing the key or clicking on the image increments its associated counter, and displays (for the images) the symbol at the mouse's pointer location. Such a project is so simple a child could use it!