I stopped off at the Tate Modern this afternoon to see The Tanks, a new exhibition space opened last month in what were the oil storage tanks under this former power station. This particular installation invites visitors to write messages on sticky notes, and to send tweets which are projected as part of the artwork. Ironically there was no mobile coverage down there so mine didn't actually send until I got up to the ground floor. And the reason there's nobody to be seen here is that this part of the gallery had actually closed while I was taking the photograph from behind a column and I could have been there all night if a security guard hadn't found me. It could have been a sticky situation.