Hi,
I have one of these locks on my front door. http://www.easylocks.co.uk/era-pin-british-standard-euro-thumbturn-cylinder-euro-thumbturn-cylinders-p-4756.html?osCsid=812520a011514705d905bfdf00e365cc
Now the other day I heard the letter box rattling late at night so I sneaked downstairs...