need a code/script to hide my ads

[leavead]

I plan to put some ads on my site that only showing up when visitors try to leave by moving the mouse toward the upper right or the upper left corner (to click the back or the x button).

Either detect mouse movement to activate ads or put invisible active spot on top of my page so when mouse over it the ads will show.

I need a code/script that I can easily insert into my page source code to make this work.

Please give me a quote, appreciate.