Getting 'rollover' to follow mouse

Hey there lovely clever ppl (butt-kissing should help)…

Please have a look:

This is just something I threw together to demo what I want.

That red keyline, I want it to follow the mouse. There will actually be about a dozen links on the left of the page and they will be static. i want it so that you roll over a blurred bit of text and the red box follows the mouse (obvously sticking to the left of the sreen) to bring the text into focus.

How can I do this? and can I still make the red box a mask for the underlying layer if the red box is animated?

Any help mucho appreciated, amigos.