MovieClip move based on mouseX position

Hi All,

I’ve seen this done all over town, but I don’t know the actual name of this effect (I think it’s mouse scrolling or something). I’m trying to make my movieclp move (left and right) based on the x position of my mouse. This is done with photo galleries all the time. The mouse moves over the thumbnails and to the right, the thumbnails slide to the left, and so forth. What’s that called, and can someone point me to a good tutorial for this??