This morning he made a "work desk" and used a wood block for a mouse. The R2D2 computer has reappeared and he's been pounding on the keys. I caught a cute moment on video (posting later) where he recited the ABC's and punched out each letter on the keyboard.
He's learned about the different kinds of computer mouse(s)- tracking ball or light. I think that's what it is. I need to ask James... He's also learned how to point and click. He's a genius.