And obviously, from our own personal point of view, the principal challenge is a personal challenge.

Having a good network can be invaluable. It opens doors for you and allows you to enter into opportunities that are beneficial to your business.

My biggest motivation? Just to keep challenging myself. I see life almost like one long University education that I never had - everyday I'm learning something new.

Happiness doesn't come from making a fortune and owning lots of possessions. 'Stuff' doesn't bring happiness. Family, friends, good health and the satisfaction that comes from making a positive difference are what really matter.

I always tell other people to protect against the downside, and not risk roughing on new ventures, but I never stuck to that rule myself.

You see, it's essential that one of us stays awake during the flight [ballon]. So, rather than using the comfortable Virgin seats which we used to cross the Atlantic, we've asked British Airways for two of theirs.

Throwing yourself into a job you enjoy is one of the life's greatest pleasures!