Looking at it from a certain angle, this block in King's Cross is slightly reminiscent of New York's flatiron building, though admittedly not quite as impressive. I love this block and the strange tower on top of it known as The Lighthouse, which has sadly stayed in a state of disrepair for some twenty years. As with Battersea Power Station, this is another sad story of lack of funds, legal issues, red tape, etc, whilst meanwhile it stands decaying and boarded up. Also like Battersea Power Station it's a listed building, so hopefully it will stay with us, though being listed doesn't seem to mean much nowadays, seeing that many of them are allowed to rot.
Though called The Lighthouse because of its shape, I've always thought of it as a tower from a surreal pirate ship. Its actual purpose is something of a mystery, with some speculating that it was once an oyster house, others that it's an architectural folly. Whatever it was used for, it's certainly unique, and with St. Pancras train station recently renovated and King's Cross station currently being given a facelift, it would be great for the flatiron block to be similarly rejuvenated.
The peg graffiti on the tower is fairly new; I've been seeing quite a few of them all over London recently.
I pinched the photo from here; next time I'm in the area I'll take a photo myself.