NOR gate S-R latch
The description of this circuit can be found in Lessons in Electric Circuits: Volume VI - Experiments book, page 337.
Note: The supply voltage of ICs was changed from the original value to increase LED currents. Moreover, the original switches were replaced by pulse sources, as by toggling switches we would restart the simulation neglecting previous state of the circuit. Further, the IC2's output capacitance was increased so that the IC1 and IC2 did not switch at the same time.