For those with programming experience, I agree with Nigel. For those who don't, it would be a good first project. A first-timer is not going to do the programming in a couple of hours.
I don't want to get into a pissing contest here, :roll: but if thup, for whatever reason, doesn't want to tackle a microcontroller, I offer a hybrid of my first circuit and k7elp60's. I think the choice of drivers is a matter of availability. I like MOSFETs because they don't have 0.75 volts of drop across them like a Darlington does. I would certainly avoid the ULN2003A in this application because, according to the datasheet, Vce(sat) is almost 2 volts at Ic=500ma. In fact, I looked at that part before settling on MOSFETs in my original circuit.
I changed the timing components on the 555 because I don't believe you could get down to 1 Hz with the values k7elp60 shows.
EDIT:
k7elp60 pointed out an error and some omissions in my schematic (see the next post). The corrections have been made below. I corrected the timing elements in the clock multivibrator and added a power-on reset circuit and an LED for monitoring the frequency. Thanks, k7elp60.