Thanks for the offer, but I'll just get some pastel card stock. The optical mouse actually works fine on the bare tabletop, but it's quieter with the card stock.

I remember trying to use a piece of red card stock once and it didn't work either. But, in that case, the reason's obviously that red lasers can't "see" red.

The bright white card stock must be too reflective. Sorta like trying to mouse on a mirror.