This should be a challenge

Here's a challenge regarding mouse movement

[adni18]

Is there a way (in javascript) to tell which direction the user has moved his or her mouse?

[DrDoc]

You can constantly check the x/y coordinates, always storing the previous value for comparison. Then, by comparing the current coordiates with previous, you'd be able to determine whether the mouse was moved up/down/left/right

[adni18]

This method happens to be a very cpu-intensive process for some users.

[DrDoc]

True... never said it wasn't ;)
But it works...

I'm afraid I don't know of another way.