Today I came across a 1982 dated 24-page booklet titled "The Radio Shack Computer Demonstrator" developed by Fred C. Matt. Section 1 was labelled "Storage Unit" and showed a series of instructions: 00 LODA,05 01 ADDA,06 02 STRA,07 ..... and further headings described registers and a comparing unit. I thought at first "Was this some sort of SBC with a monitor/assembler?" But reading on, it became obvious that this device was made out of _cardboard_ with sliding tabs for a line counter, and registers which were written to with a pencil! Has anybody managed to find/keep one of these things? Sounds a neat little souvenir from the period. And if anyone followed through the steps, they would indeed have had a good introduction to programming a microprocessor in assembly language. Would be great for kids even today - except I can't see many having the patience or interest unfortunately. Phil Brisbane, Australia