When I was at work I used to have a colleague who used to actually make his sandwiches at his desk (opposite mine!). He'd go out to the supermarket and buy a proper loaf, ham, tomatoes etc. He kept butter and leftovers in the office fridge. He'd sit at his desk, get out a bread knife and slice up the loaf, spread the butter, slice up the tomato with a different knife and put it all together [ shock]
His computer keyboard was always full of breadcrumbs 