How to teach my 8 years old son programming

Hi,

I would like to introduce my son to programming. He keeps asking me what I do at work and when I started talking he was very interested.

Are there any programming tools, languages etc that would help me to introduce him to programming. I am talking about simple stuff like program robot to walk couple of steps, turn right, pick up box walk, turn left, drop the box. You get the picture.

Thanks a lot,

T.