In reply to Lemony:
True, but i'll be surprised if that gets forced to 'normal' self-employed workers for quite a few years to come (i.e. people paying CIS which are on the bottom rung and very unlikely to be pushing over the VAT threshold) as the biggest acknowledged issue with it is the outlay necessary to set up at home and lack of IT skills to personally adapt smoothly.
Regardless, when/if that gets fully introduced HRMC will (allegedly) provide software to download free of charge