I was following a thread and was amused by some of the answers. I'm interested to see how much people know.
Though it is very difficult for someone that you are using a bitcoin or not because bitcoin is very anonymous and it strongly believes in users satisfaction, its oeer to peer transactions enables customers to have very safe and confidential transactions but as we all know that nothing is impossible in this digital world, almost every thing is cracable , the all you need is to be little more careful with your every transaction and most importantly you should be very careful with your keys.