The 74HC595 that kchriste mentioned is a latching shift register, it has a built in storage register that holds the contents of the shifted data until a third line is toggled then the output latch is updated. It requires one extra I/O line for operation but the latch updates all the lines at the same time. Perfect for driving relays such as this to avoid any possibility of triggering the relay accidentally. You could operate it as a standard shift register by tieing the update to the clock line if needed.