Another fun read: Civilization-Level Quantum Suicide

Quantum Suicide Reality Editing

If you accept the idea of quantum suicide then you should be open to the idea of using it for editing reality. You could construct some system that monitored events for you and would immediately cause you to cease to exist if events did not happen as you wanted them. The idea would be that you would continue to exist only in those future worlds in which events happened as desired, so that from your point of view, events would always happen as you wanted. You would be using quantum suicide to control your reality.

Quantum Suicide Computing

Suppose you had some computing problem which would take a long time to solve, but you have some way of checking possible answers. You could set up some system which uses quantum events to generate a random answer to the computation and then automatically causes you to cease to exist if the answer is not the correct answer, or if it is not better, in some sense, than the previous answer that you obtained. The idea would be that future worlds would exist in which all possible answers were generated and you would only exist in those worlds where the answer was correct or better than previously generated hours, thereby giving you the perception of having enormous computing power.