El Salvador's president made Bitcoin legal tender, now he wants to build a city. Joe Tidy speaks to Salvodoran-American cryptocurrency enthusiast and investor Gerson Martinez about the Central American country's experience with Bitcoin since its introduction earlier this year. Plus 193 member states of the UN agency Unesco say they want a more ethical approach to the development of artificial intelligence. We hear from Unesco's Gabriella Ramos about the problems with AI use today. And our own Jane Wakefield investigates the community of tweeters and YouTubers helping others find the latest Playstation and XBox consoles amid a global computer chip shortage in the run-up to Christmas.