There is a disease spreading across the Tube network. But it is a pleasant disease. A disease that you'd be happy to take home to your elderly relatives. It is the disease of positive thinking.

When I moved to Clapham (almost two years ago now, how time flies), my tube station of choice became Clapham North. I could have continued travelling from Fulham Broadway, but that would have involved a really long walk.

Clapham North at the time had two very nice features. Firstly, they played classical music, and secondly, they had a quotes board. Or, more accurately, a service information board repurposed to provide inspiring morsels of thought on a daily basis.

These would vary from a simple suggestion to smile, through literary witticism and on to downright evangelism. Something for everyone.

It has become a feature of the community (albeit one we don't really acknowledge in conversation), a chance for an individual to share a single sentence with thousands of commuters each day. A sentence that really meant something to the marker-holder, and would hopefully brighten up the readers' day. 

One could be cynical, and say it is just a distraction to make visitors slightly less aggressive. But for a few seconds each day, I would stop at the top of the escalator with a few of my fellow travellers, and we would share a moment, however brief and silent.

Of course, with everyone stopping to read the day's message, there was a bit of a bottleneck. But the Health and Safety mob in their wisdom chose not to remove it outright (contrary to the current popularity of kneejerk reactions), and it was moved a couple of feet to the left.

And the trend seems to be catching on, with Stockwell and Clapham Common stations getting their own quotes boards. The board at Stockwell is pictured on the right - with possibly my favourite quote. Perhaps one day, this will be TFL policy.

So be on the lookout for these pearls of wisdom (second-hand though they may be), and please let me know where else they crop up.