They aren't too uncommon, Fidelity has had one for a while: https://www.fidelity.com/cash-management/fidelity-cash-management-account/overview https://www.fidel

They aren't too uncommon, Fidelity has had one for a while: https://www.fidelity.com/cash-management/fidelity-cash-management-account/overview https://www.fidelity.com/cash-management/fidelity-cash-manag...