Another topic that has cropped up recently on several forums including the vintagemicrocar forum which has been around for a few years is the use of portable high-power laser equipment to remove rust or old paint from car bodywork.
https://youtu.be/dZ_90920Zbghttps://youtu.be/CLaBFkeHG0AThe results are dramatically impressive, but the cost of the equipment at the moment probably puts this service outside the range of most car restorers. There are also legal constraints (in the UK at least) on the use of lasers this powerful outside of industry, so probably not something we'll be seeing in Halfords for a while.