Are special shampoos and coatings any good at cleaning and protecting your car?

They're all over Instagram: washes, foams, and ceramic coatings in a rainbow of coloured bottles that promise to give your car that showroom shine. For listener James - a driving instructor - the question is whether they're worth the money, or if an ordinary bottle of washing up liquid will do the job. To find out Greg is joined in the Salford studio by materials scientist and vehicle coatings researcher at the University of Manchester, Dr Beatriz Mingo, as well car expert and TV presenter Tim Shaw. Each episode Greg investigates the latest ad-hyped products and trending fads promising to make us healthier, happier and greener. Are they really 'the best thing since sliced bread' and should you spend your money on them? At Sliced Bread, we're hungry for your suggestions so we can keep making fresh batches! If you’ve seen an ad, trend or wonder product promising to make you happier, healthier or greener, email us at sliced.bread@bbc.co.uk OR send a voice note to our WhatsApp number, 07543 306807. RESEARCHER: PHIL SANSOM PRODUCERS: PHIL SANSOM AND GREG FOOT

Lech Walesa: Inaugural lecture of the Millennium Lecture Series, October 8, 1999