I am surprized the friction type vacuum hasn't made a comeback-they would filter the fine dust better than sweepers and can be used in places such as restuarants and movie theaters without disturbing patrons.The machines could combine the advantages of sweepers and vacuums.And of course--no shock hazard or power cords.also maybe good for office cleanup under cable laden desks.No powered roller brush to foul the computer,phone and power cords lurking around and under office desks and tables.