A holiday in Sicily dominated by the smouldering crater of Mount Etna has given my 10-year-old son (OK, and me) a thirst for information on volcanoes. This site - one of hundreds - provides a gentle introduction to the explosive world of online volcanology.

You can monitor active volcanoes around the world, choose your favourite crater and find out as much as you are likely to want to know about its current and past eruptions. There are some truly terrifying photographs.

Best of all, there are links to a number of live “webcams” trained on active peaks by local volcanologists. Which is why I can get a better view of Etna’s billowing Bocca Nuova from a desk in Wapping than I had from the poolside bar in Taormina.