An interesting take on this is in the Culture series from Iain M. Banks. The AI minds, who for all intents run the Culture civilisation, constantly spawn virtua

An interesting take on this is in the Culture series from Iain M. Banks. The AI minds, who for all intents run the Culture civilisation, constantly spawn virtual universes to test hypothesises. Some shut them down after running the sim, some feel morally obliged to keep them running... Also, if someone's suddenly jerking the strings in a game, it usually means they're bored and it's only a matter of time before they press one of the "godzilla invades", "aliens attack", "mass-tornados" buttons.