For your favorite mathematician (a.k.a. mathemagician), how about a dishtowel, pencil case, or mug? Or all three? Chalk white lines on a black background evoke memories from past math classes, and no matter if you liked/loved/hated them, you (or someone you know) can still enjoy a little math imagery with appreciation.
Math Mug, $12.95
Math Canvas Pencil Case, $17.95Available from Fishs Eddy, $12.95 - 17.95.