How do I create this effect

Does anyone know of a tutorial that will walk me through creating the following effect.

OPTION 1 | OPTION 2 | OPTION 3 | OPTION 4

   ^

In the above example I have four options (buttons), I want the little cursor below ‘option 1’ to follow where the mouse goes. For example if the user moves across to option 4 the little ^ follows it. I have seen this used on a few sites and would like to mimic/copy the effect.