Gumby's little sister is named Minga, which also happens to be a very common Italian swear (meaning either "dick" or "to urinate").
In The Movie, when the robot Gumby is melting away, the lightsaber it's holding is positioned over its crotch. Either that, or it's a Spaceballs reference.
Awesome Music: Most, if not all, of the music in the movie, but especially The Clay Boys' songs!
The John Seely/Capitol stock music used in the 1950s shorts is also quite memorable, even if it mostly wasn't composed for the series.
Cult Classic: The movie is one of the more fondly-remembered non-Disney animated features from The Renaissance Age of Animation and enjoyed a healthy life on cable TV in the '90s. RiffTrax even tackled it in 2021, the first time they've riffed upon a fully-animated feature.
Faux Symbolism: The official companion book, Gumby: the authorized biography of the world's favorite clayboy, written by Art Clokey and others. Basically, Gumby's mind is free.
Ho Yay: This may be a bit of a stretch, but has anybody noticed that Blockheads G and J are never apart? And that J seems to take G's abuse a bit too submissively?
Narm: In "The Magic Wand", Professor Hocus-Pocus accidentally leaves his magic wand at Gumby and Pokey's lemonade stand. When the wand goes crazy and accidentally knocks Mrs. Gumba's good pitcher off the stand, Pokey calmly says "Look out" right before it smashes to the ground. Only afterward does Pokey actually show any concern...
At the end of the very first serial "Moon Trip", Gumby's parents try to resuscitate him after he's been stranded on the moon. The sequence is mostly dialogue-free and has a rather tense and unsettling atmosphere.
A piano-playing boy in "Small Planets" who goes feral when his arpeggio is interrupted. The boy sounds like a kid in the 1960s even though he transforms himself. In the same episode repurposed for the 1980s, the boy now sounds like a young man, at first, but when he transforms into a beast, his voice now sounds very deep, beastly, and menacing! Scary!
No Problem with Licensed Games: Namco headed up a Gumby game for the Game Boy Advance titled "Gumby vs. The Astrobots", a side-scrolling platformer where the Blockheads use robots to kidnap Gumby's family and friends, leaving Gumby to save the day. Aside from being a bit repetitive at a few points, the final game is actually pretty decent.
In certain scenes in which Gumby and the other characters walk or drive into a book, the animators used different models for the characters and vehicles. These models are either crudely made or 2D!
The same goes for the shrink/growth episodes. In the 1960s episode "Chicken Feed", the growing effects with Tilly the chicken are created with badly colored two-dimensional pictures of Tilly. Also, in the 1980s episode "Shrink-a-Dink", the growing/shrinking scenes (specifically with Gumby, Goo, Prickle and Professor Kapp) used crudely made models in each frame.
Any scene which requires Motion Blur is inevitably just live-action footage of the clay model being moved in real time. The most egregious is in "Rain Spirit", where Gumby diving into a pool is achieved by literally filming his model being dropped into the water as Pokey remains completely motionless.
In the 1980s episodes, all voice-acting has a strange reverb effect to it for some reason.
When Gumby and Tara are dancing in the hall of giant Pokeys during the "Take Me Away" scene from The Movie, the animators' tools can be seen popping in and out of the top right corner of the screen.
played at the park in the movie carries a similar beat to "Paradise City" by Guns N' Roses.