The principle: fund OS and other government data collection agencies from direct tax funding (rather than by charging every user, as at present) and make non-personal data such as OS and Met Office and UK Hydrographic Office and.. so on available for free for any sort of reuse without licensing restrictions.

Now if that were in place, you’d have Virtual London and a gazillion other projects to boot.

OSM is a nice idea, but can’t do the scale and accuracy of OS, and anyway relies on government funding – by the US of the GPS system.