On "Best Friends Day," Patrick gives SpongeBob an enormous wad of used gum he has amassed over his entire lifetime (fondly referred to as "Gummy"), and SpongeBob finds it a better gift than his own (a robotic butler). However, when he takes it inside, he realizes how disgusting it is, making him throw up in his mouth when he smelled the moldy pizza on Gummy, and it even starts to scare him, with a pair of underpants crawling out of the gum and saying in a demonic voice, "You're not Patrick!" First, SpongeBob tries to throw it away, but Patrick catches him in doing so, and he says that he was dressing it up with the garbage can. Later, SpongeBob tries to bury Gummy, but Patrick catches him again, and he says that he dug the hole to be able to look at Gummy from below. Patrick insists that it must be displayed properly, and places it above SpongeBob's doorway. SpongeBob next tries to dispose of it in the night, and in the process frees several fish who were literally trapped inside it. He tries to pull Gummy off of his house, and fails, destroying the ball and getting stuck to it in the process.
The next day, Sandy visits SpongeBob's house to see it covered in the sticky remains of Gummy, with SpongeBob hanging above his doorway. She tries to free him by lassoing a piece of Gummy onto a passing truck, which is almost able to pull it away, but is ultimately pulled in by it, hitting SpongeBob's house and causing the gum to explode, completely covering the houses of SpongeBob, Squidward and Patrick, and trapping Squidward and Sandy as well. Patrick then appears, and SpongeBob tells him he can have Gummy back. Patrick then wolfs down all of the gum making him super-morbidly obese, freeing SpongeBob, his friends and their houses. However, he then hiccups a massive bubble, which explodes and covers the whole town in gum and Patrick yells that this is the Best Friends Day ever.
Season 4 Volume 2 and The Complete Fourth Season DVD covers are based on this episode. The Season 4 Volume 2 DVD features Plankton on the backside being stuck in the gum, possibly as a joke. However, he did not appear in this episode.
For some reason, along with "Best Day Ever," this episode did not air in the Netherlands until May 9, 2010. Although, the rest of season four had already aired in the Netherlands back in 2006.
This episode premiered in the Netherlands on Rosario Dawson's 31st birthday.
The German title, "Gummilein," is also to the German name of Gummy.
In the Croatian dub, the episode name is "Žvaka" or "Gum."
This episode was released on the Season 4 Volume 2 DVD box set before it aired on TV in the USA.
The name of this episode is a possible reference to either "The Gift of the Magi," a short story written by O. Henry, or the phrase "the gift of gab."
Robo 2.1 is similar to C-3PO from the Star Wars films as he has a similar voice and said a similar phrase to C-3PO's when introduced in the episode.
Strangely, he also slightly resembles R2-D2.
The concept of this episode is similar to that of the 2004 video game Katamari Damacy, in which a ball gets bigger by having more things stuck on it.
At the end, during the cleaning of the gum, Patrick ate some of the gum like Pac-Man.
Patrick destroyed his rock to get Gummy out to SpongeBob. The next time there is an outside scene, his rock is back the way it was.
During the opening shot (including near the ending), the windows of SpongeBob's house and the chimneys are on the wrong side of his house.
When SpongeBob shows his present to Patrick Star, Patrick's mouth disappears as the camera panned over to Robo 2.1.
The truck driver calls his truck "Old Blue" even though it's red.
When everything gets covered in gum, the flower on Sandy's helmet swaps sides.
Before SpongeBob gives Gummy back to Patrick, he tells him that it's still Best Friends Day. However, the episode took place over two days. This error is further reinforced by SpongeBob saying "Well, it's still Best Friend's Day..." close to the end of the episode. As a result, SpongeBob could have been trying to trick Patrick into taking Gummy back, or Best Friends Day is a multi-day holiday.
When Patrick cleaned the gum, SpongeBob's house's windows were backwards.