  What is the maximum number of holes enclosed by a $d$-dimensional polyomino
built of $n$ tiles? Represent this number by $f_d(n)$. Recent results show that
$f_2(n)/n$ converges to $1/2$. We prove that for all $d \geq 2$ we have
$f_d(n)/n \to (d-1)/d$ as $n$ goes to infinity. We also construct polyominoes
in $d$-dimensional tori with the maximal possible number of holes per tile. In
our proofs, we use metaphors from error-correcting codes and dynamical systems.
