Pop Culture Holiday: In some corners of the fandom, January 29th (the original air date) is celebrated as Threshold Day, with fanart, memes, and a general consensus that Chakotay made the wrong call in leaving Janeway and Paris' offspring on the planet.
So Bad, It's Good: Tom Paris travels at infinite speed, becomes a catfish, turns Janeway into a catfish, and they have baby catfish. And they're cured by injections of antimatter.
The entire episode isn't good by any means, but go into it looking for something to ridicule and laugh at, maybe with some drinks and friends, and you'll be entertained as hell.
And someone took it upon themselves to create a TAS version of this scene.
Took the Bad Film Seriously: The makeup crew created some darn impressive prosthetics to depict Paris' transformation, and Robert Duncan McNeill acts his heart out.
They Wasted a Perfectly Good Plot: The episode sets up as a promising bit of Character Development: Paris has well-established insecurities thanks to his demanding father, and he's driven to try something incredibly dangerous in order to redeem himself. Also, early in the episode Kim (who manages to narrowly escape being the Butt-Monkey for once) is initially chosen over Paris as a better candidate for the Warp 10 test flight, which could've been an interesting test of their friendship. Instead, well... catfish babies happen.
Visual Effects of Awesome: Regardless of the episode's reputation, it still gets universal praise for the Body Horror makeup effects, which won the episode an Emmy.
a TAS version of this scene.