Cost of motion sensor

Nowsaday the cost of the motion sensors are getting cheaper and cheaper. Because there are getting more and more new technologies in the market. until now motion sensors are not outdated yet and it is getting famous right now, because right now many company especially for those invent games company are using motion sensor combine with their product, for example Wii and PlayStation 3. These will make the player to play the game easilly. In conclusion motion sensor is not expensive nowsaday.