Boards
On Friday night, I'm pretty sure I found one of these...
http://news.bbc.co.uk/1/hi/entertainment/arts_and_culture/7730285.stm
It was just propped up against a wall in Shoreditch. When we came across it, it would've been about 9pm, so it does fit the description
Sell it now, or hold on to it for a couple of years? It is actually quite a cool painting too, so that's nice