Budget airline Wizz Air last year launched an 'all you can fly' deal for just £426 a year - with customers able to jump on unlimited flights. Last week, the airline celebrated a year since the scheme was launched - and Wizz Air said it had been 'overwhelmed by the extremely positive response' for the concept. Through the scheme, you only are able to book flights between three days (72 hours) and three hours before departure. Another catch is that, while £426 a year sounds like a great deal, Wizz Air flights are cheap anyway. So many argue the 'all you can fly' scheme is a neat way to top up sales for the roughly 10 per cent of seats that never get sold.