I am speaking about the psychology of dreams at the British Science Festival 2012 in Aberdeen at the weekend. Do come along and say hi. Details here.
OK, here is the puzzle. As ever, please do NOT post your answers, but do say if you think you have solved the puzzle and how long it took. Solution on Monday.
If you turn this number upside down or reflect it left-to-right you get 11 either way, but the original number is not 11. What is it?
I have produced an ebook containing 101 of the previous Friday Puzzles! It is called PUZZLED and is available for the Kindle (UK here and USA here) and on the iBookstore (UK here in the USA here). You can try 101 of the puzzles for free here.