While Sliced Bread takes a break we serve up… Toast. A study of the spectacular failures of wonder products and businesses which had promised so much to consumers.

You can contact us at toast@bbc.co.uk

In each episode, the presenter and BBC business journalist, Sean Farrington, examines one big idea which ended up toast, examining the reasons behind the failure and discovering what can we learn from its story today.

Sean unpicks all the early optimism, hype and ambition, speaking to expert commentators to discover how they view things now and what, if anything, could have been done differently.

Sean is assisted by the self-made millionaire and serial entrepreneur, Sam White, as together they try to work out what went wrong.

This week, Sean and Sam look into the Sinclair C5 - an electric vehicle from the 1980s which promised to revolutionize personal transport.

They get a first-hand account of what happened from the former Managing Director of Sinclair Vehicles Ltd, Barrie Wills, and hear how the Isle of Cumbrae became a hotbed for the Sinclair C5....until the little vehicles started breaking down all over the island.

They also speak to Grant Sinclair - nephew of the C5's inventor, Sir Clive Sinclair - and hear how he has devised a new and very different take on the C5 which he plans to launch soon.

Presenter: Sean Farrington Producer: Jon Douglas

Toast is a spin-off from Sliced Bread, the series in which Greg Foot investigates the latest so-called wonder products to find out whether they really are the best thing since sliced bread.

Sliced Bread returns for a new batch of investigations in May. In the meantime, Toast is available in the Sliced Bread feed on BBC Sounds.