Well, my contact at this client has just pressed a bottle into my hand -- a nice little Speyside single malt. I reminded him that we intend to invoice him for my time. I pointed out that I'd thoroughly enjoyed the exercise. I observed that doing this sort of thing was, in fact, my job. Nevertheless, he says they're most grateful that I came out at short notice, and that I stayed until the job was done. So I thanked him very much.
I like my clients.