Why is the door of "oliver house" on moorgate covered in pennies ?

Question:

Why is the door of "oliver house" on moorgate covered in pennies ?

the door of the place called oliver house on moorgate (between moorgate and old street station, right next to the old street bus stop towards london bridge) is covered with 1 penny and 2 pence coins stuck in a very orderly manner all over it. i have been walking past this door for months and only noticed it last week and it has been puzzling me ever since. it even looks like the door is not even actually in use and has been locked shut from outside and barred...

can anyone explain what this door represents ? am i the only one to have noticed it ? a few days ago i stopped and took a picture and people around me didn't even seem to notice what i was trying to take a picture of.

Best Answer - Chosen by Asker:

I have no idea, still looking and will try and come back to you...