Last winter I began filling a large, old-fashioned American milk bottle, the kind that holds a quart of liquid, with small change in order to give the contents to charity. For 12 months, every 1p, 2p, 5p and, yes, 10p that came my way went into the bottle. The 10ps felt rather reckless, they are still some use after all, but hey, I thought, let's be generous.

Each evening, when I got home, with a warm glow of satisfaction, I'd drop my shrapnel into the bottle. Not only that, such was the pleasure I derived from this activity that if I hadn't managed to come by some change that day I'd pop over to Mustafa's for a pint of milk to generate some. This became a mild obsession. I'd even badger colleagues to swap me a twenty for their smaller stuff.

Slowly the bottle got heavier. Periodically, I'd pick it up and shake it vigorously to settle everything down and create more room. By the time I came to empty my stash in mid-December I could barely lift it. Just to fish and flick all the coins out through the bottleneck on to the table took half an hour. The cold heap in front of me looked, felt, smelt even, like a small fortune.

My mother-in-law volunteers for the Jacob's Well Appeal based in Beverley in my native East Yorkshire. I'm not precisely sure what the appeal does but it sends a lot of bedding and medicine to children who have neither. At Christmas, I shovelled my contribution into a carrier bag, lifted that bag carefully into two others in case of splits, heaved the whole load into the car, took it up north, handed it over. Someone then spent a long time counting it, bagging it, taking it to the bank, turning it into blankets and bandages.

Now the point of reciting all this is not to big myself up, quite the opposite. Because not long after I'd donated the fruits of the year's metal-collecting to Jacob's Well, the charity sent me a nice letter to say thank you. How much do you think Lord Bountiful had raised? It was every randomly received 1p, 2p, 5p and 10p for a year, remember, plus the others I'd deliberately farmed. Take a guess.

Seventy-five quid is the answer. The year before, when I'd felt a bit tight and hadn't done 10ps, it had been £31. Now, of course, it all counts, and better to have spent £75 thus than bought more books I'll half read, CDs I'll half listen to or presents my children will half play with, but still, £75 for a whole year? £1.44 a week? Scarcely 20p a day? Next year I'm going to have to siphon off twenties. To muster a really significant sum, I'd have to take all the fifties and pound coins out of circulation too. Give away every £1 coin I ever get hold of? That's going to hurt.

Danny Finkelstein, my editor, wrote here yesterday that he wants to create a new social norm, whereby it becomes the done thing to donate 1 per cent of your gross income to charity. It's a laudable goal, boss, but anyone who thinks they can do it with loose change is in for a shock. Probably best to write a cheque.

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