An energetic hamster called Elvis gave a budding engineer a bright idea for charging his mobile phone.
Peter Ash, 16, from Somerset, realised that Elvis's fave activity of playing on his wheel could be used to create electricity to charge his mobile.
As part of his GCSE coursework, he created a device where he gets 30 minutes of talk time for every two minutes that Elvis goes for a spin.
Peter passed his GCSE electronics today and says he has plenty of other ideas.
He told Newsround: "Elvis is in his wheel for four or five hours a night, keeping my sister awake. I thought it might as well do something good!"
As for his other bright ideas, Peter said: "I don't want to tell people about them in case they don't work - or even worse they might steal my idea!"