Have you ever had that feeling like someone was watching you?

If a controversial new billboard goes ahead, it may be more than just a paranoid concern.

A new technology is being introduced to the world of billboard advertising, this technology will video you as you walk past the billboard, and will aim to determine things like your age, gender, and it will even monitor facial expressions to determine how you reacted to the ad.

This is the bizarre invention of a small team of entrepreneurs called Quividi, who aim to tailor specific ads to the person walking past.

The technology has already been tested in Ikea and McDonalds in Europe, and it has infiltrated America already, being tested in Philidelphia station earlier this year.