In economics, one of the most important concepts is 'opportunity cost' - the idea that once you spend your money on something, you can't spend it again on something else.

Gone are the days when your indiscretions at university were recorded in a roneoed college newsletter of which there is only one copy left tucked in a filing cabinet at the back of a library. Today that same college newsletter is online, accessible by the whole world now and forever.

Newspapers are busily experimenting with different models. Traditionally, and I suspect in hindsight very mistakenly, online news was free. And once given free access readers felt it was their entitlement.

China and India will take the global leadership on climate change: they are suffering for it.

I've always been prepared to put my money where my mouth is.

The proliferation of outlets that digital technology has enabled has itself contributed to the changing nature of what we regard as 'news' and the way in which many citizens perceive politics.

It's really corny to say, but if you are happily married and have good kids, that is about 98 per cent of what you should be seeking to achieve.