http://www.bbc.co.uk/news/uk-21614774 (http://www.bbc.co.uk/news/uk-21614774)
All of my wrapped Christmas presents were opened once by Security when they travelled on their own from Paris to Tunisia.
On a flight from Dublin to Fuerteventura I had to sign giving permission for my bag to be opened. They showed me the x ray picture of a large item which was a cause for concern and asked in advance of opening the bag what it might be...... it was my 10 litre bucket of white paint. :D