**Update** - Added a few things:
-Capital letters now transfer (yay)
-You can input the number rather than using the buttons
-The buttons don't mess up
Heres a "program" I made to decode/crack codes based on alphabet pushing system. Just type something into the textbox on top then change the number to something (0-26) and it will output the code in the bottom textbox.
For someone to "crack" the code, they will need to know what number you used.