Yes, there is someone hiding in this optical. Only the the very observant will see. It's a bit scary.

Car manufacturers seem to like optical illusions. We have recently had the Honda video with some great tricks and here is an older advert from Audi attempting the same. Perhaps its the same agency. Which one do you prefer?

Not an illusion - more a play on words.

Here is our latest upside down illusion illusion. Today our subject is L J Rich, freelance presenter music composer and hacker. Plus being an excellent tweeter. @LJRICH

Can you see the hidden image? Once you've got it, you'll never lose it. Click on the spots to reveal.

These guys are climbing the support cables on the Brooklyn Bridge. But can you pick the climber the same height as the man at the bottom left, A, B or C?

All we have here is a red square turning on a black and white spoked wheel, but we find it mesmerising and the square looks all irregular.

This illusion will make your eyes go funny. But it is definitely worth the trouble. Just stare at the beating heart at the center of the grid. Count 30 beats then look at the back of your hand for a few seconds. Wow!

Less an illusion, more a cool video with great artistic technique. 

Just put your mouse over or click the picture to turn that mound upside down. Wow.

I saw this illusion on the internet and found it immediately striking. The patterns were moving all over the place really strongly. I have been looking at this type of illusion for many years and have even produced some myself, and I have noticed that they are not always as striking to everybody, some get it some don't. Also they are not always the same to me, one day they are strong the next not so much. I must do a Spy Blog about it one day.
Anyway I do not know who designed this one, so if you do let me know so I can give credit where credit is due. - Spyman

Just run your mouse over the picture to reveal the answer.

If both cars leave at the same time and travel at exactly the same speed, which will get to its respective chequered flag first? You guessed it, they both would arrive at the same time as both tracks are equal length.

This three handed automaton is made soley from wood. It was manufactured by Peirs Heldorf and exhibited in the Pers Mechanical Cabinet room in Sweden. The articles are all inspired by Christopher Polhem, an 18th century inventor. How it moves the ball is anyone's guess!