I recently discovered that the thing I most want to do with my time is toss bean bags into a box. The box is wedge-shaped and there are holes cut into it, numbered 1, 2 and 3. The bags are just the right weight for throwing: somewhere between a tennis ball and a cricket ball.

I don't have to do anything complicated with them, just get the bags into the holes. I stand eight feet away. Then ten. Then more.

No one is safe. Everyone who walks past me is pressed into joining the game. People start avoiding me. I don't care. I'm completely addicted.

This comes as no small surprise.

I like to collect rocks. I enjoy experimental cooking (sometimes known as 'things that didn't work out'), and experimental eating (sometimes known as 'restaurants that didn't work out'). My Scrabble is appalling but that doesn't stop me. I like untangling string and knotted necklaces.

Given the sedentary nature of most of the things I enjoy, I'm taken aback by my impassioned delight with the bag toss. This is, at most, mild physicality. I'm not doing hurdles or ballet. The thing with the bag toss is, I suddenly realise I'm playing. And how often do I do that?

According to studies on the importance of play in our lives - for adults as well as children - even the arguably dull things on my fun list can be considered play. I'm not doing them for material gain or fame, but somewhere along the way I think I stopped seeing them as fun. And fun is the defining characteristic of play.

While adulting, we tend to forget to make time for fun. For play. If we are part of a Friday-evening football team, we tell ourselves it's for exercise or to destress. If we join a book club, we want to think we're doing something intellectually improving. We may enjoy these things, but we don't do them simply for the joy of it.

At some point in this whole living business 'fun' became superfluous and 'joy' (bizarrely) took on some really serious connotations. Joy is for weddings, brand-new babies, graduations, promotions. We're always hearing we should find joy in simple, everyday things, but I don't know many (read 'any') people who do.

But I digress. I want to play bag toss. I want to play it with others, but I'm ok to play it by myself. Because, for reasons yet to be discerned, it's the most fun thing I've done in years. And I love that I have no reason at all to do it.

Play and play-therapy are discussed and deployed for mental development, creativity, and stress release. According to the National Institute for Play (NIFP) in the US, play 'generates optimism, seeks out novelty, makes perseverance fun, leads to mastery, gives the immune system a bounce and fosters empathy.'

And that's great. Great for grown-ups and children. Great people trying to form stronger ties in their personal and professional relationships. Great for developing all sorts of interesting parts of your brain.Play is good for us - you got that.

But there is something else, I think. There is somethin