i also do the 4 * wireless mouse thing... works great. Even on moniters with different size, i got 3 x 15" and one 19", as long as your screen res is the same i had no problem with the mouse going off sync. And then again it's not that hard to just resync be draging the mouse to one of the 4 screen coners....

Haven't tried any area spells though.. but i guess as long as your view is the same there sould be no problem...

// Z