I went into town today to do a few 'messages' and did a bit of camera browsing. Surprisingly I came away empty-handed.

While walking about I came across this van with some rather unusual graffiti. Beta-gamma-alpha-chsi-theta? And that might be an uppercase delta on the second row. And why the grids?

Relatively sensible explanations I have come up with so far range from someone acting out a Dan Brown novel on the streets of York to a Maths student doing part-time work at the BT exchange. The more exotic include phone-hacking and secret codes.

Now I need to find somewhere to leave a reply ...