This paper summarizes results of the 40-year studies on replication and recombination of RNA molecules in the cellfree amplification system of bacteriophage Q. Special attention is paid to the molecular colony technique that has provided for the discovery of the nature of ''spontaneous'' RNA synthesis by Q replicase and of the ability of RNA molecules to spontaneously rearrange their sequences under physiological conditions. Also discussed is the impact of these data on the concept of RNA World and on the development of new in vitro cloning and diagnostic tools.