I am a big fan of youtube! It can be used for so many things – whether it is curing me of boredom one afternoon while I am waiting for the train or helping me visualise how to fix a piece of equipment (e.g. most recently – the lawn mower). I also really like it as a way to share information to students across the globe – check here: https://youtu.be/CkMrrZhxC4g
it’s my video of a stirling engine!