One thing you can never give enough of is art supplies. 2D animators go through
non-photo-blue pencils like mad. If your animator has an artistic bent beyond animation, then you can also pick up some
inking pens,
brushes,
pencils,
pastels,
sketchbooks,
markers,
color pencils, and paints (
watercolors,
acrylics, and
oils are all popular).