WolfishMusings — “My tefillin are square.”
Very good. My tefillin are cubic. Makes me stand out.
talmud — “is it true that they found very old pairs of round tefilin?” Yes, I also saw that, but they were really cylindrical.
The matza is close to circle shaped. But the Kiddush Becher is technically an octagonal prism, over a cylindrical base.
The Beitza is approximately ellipsoidal.