I find overloaded operators very useful in the limited context of mathematical objects such as vectors and matrices. They can make these kinds of formulas more legible IMHO: I'd rather have

$z = $x x $y / ($x . $y)
[download]

than

$z = $x->cross($y)->divide_by($x->dot($y));
[download]

(See the Math::VectorReal module, for example).