Raspberry Pi has announced its intention to float on the London Stock Exchange and it is thought it could be valued at up to £500million. The Cambridge company, which produces hugely popular low-cost computers, said the IPO would help it continue expansion and aid the Raspberry Pi Foundation – its charitable arm – to “double down on their outstanding work to enable young people to realise their potential through the power of computing”. Raspberry Pi has sold more than 60 million computers since launching its first credit-card sized board in 2012 and has exposed millions of young people to codi…