GoCardless has become somewhat of a poster child for the London fintech scene. Offering an alternative to card payments, the startup provides a simple way for businesses to set up and accept bank-to-bank payments online (also known as Direct Debit), and is now processing £1 billion worth of payments annually. That’s up from £500 million in July — a figure that co-founder and CEO Hiroki Takeuchi tells me is on track to double.