I often wonder what the true cost of going to work really is. I’m thinking in particular of everything that comes on top of your commuting costs and the clothes you wear.

If you are carving out a career, or simple trying to maintain one, you’ll be spending a certain amount of time and money on your network. Whether it’s 2MB of data for Skype, a £3 coffee or a good old fashioned lunch (liquid or otherwise) – none of this is free.

Not-quite-official conferences, travel and a bit of shoe leather – not everything can be lost on an expenses chit. And why should your employer foot the bill for everything?

I think there is an opportunity cost that some people absorb. Maybe it’s their personal equivalent of a ‘new business fund’. They invest in that coffee, bus ride or flight, on the off chance that it may lead to something exciting in the future.

In an age when it is difficult to be certain about work, this sort of approach is invaluable. In my experience it is also what separates people in the workplace.

I am not saying for a minute that those who spend money on buying other people lunch, or lavish coffees on their contacts, will have any more chance of progressing a career. But it represents a mindset that cannot be ignored.