The longevity of Asterix and comic books.
I loved the Asterix comics growing up, and found that I loved re-reading them just as much even now. They're still hilarious, and possibly delight me even more now. My comics have also stayed in remarkably good condition.
I also realized that I'd read these for the first time nearly a quarter of a century ago (handwriting on the inside flap is my mother's, I think the "SSS" in pencil is me) - and that the very first one was written most than half-a-century ago. Great art lasts which is unsurprising; but even reasonable quality paper lasts -which is a little more surprising.