Game Maker by YoYoGames had a good system called 'Drag And Drop' where certain icons = certain pieces of code, with just simple text boxes to fill in.
Like to create an instance in code is: Instance_create(x,y,obj) so the x co-ords, y co-ords and what object to spawn.
In DnD you just drag and drop the 'instance create' icon, then theres a textbox for x, textbox for y, and a drop-down menu for you select which instance it should create.
That's a basic example, but DnD can be used to make hard commands relatively easy.
I think the Amiga actually already has one like this, but i found it hard to use.
Not sure if this is what you meant by your question.