Snake for the CASIO fx-CG50 graphical calculators.
Connect your calculator to your computer using a Mini USB cable. A menu should appear on the calculator - press F1 and the calculator should appear in your computer like a removable drive. Drag and drop a compiled .g3a file into the root directory and eject (on Windows, right click on the drive in Explorer). It should be at the end of the main program menu.
.g3a files can be compiled from source yourself (see below) or downloaded from the releases page.