“Darmok” is Internet favorite, about a species which language is exclusively in analogy that the translator could not be set up, and they decide to kidnap Picard to establish vocabulary over a campfire.

There were couple episodes in Voyager in which aliens deem humans interesting but lesser, and tries to experiment or study on crews. One that I remember ended up in a ship self destruction, in another the doctor leaving his copy. As to why they didn’t simply ask Borg for a zipped archive, I don’t know.

The Dominion commanders throughout DS9 must have made similar remarks, and so should Cardassians have. Q would outright say so in spite, corrupted Data might. Maybe combination of those? Or maybe I’m just a suboptimal Trekkie :p