The Grim Adventures of Billy and Mandy Season 7 Episode 10

The song Velma sings to call forth spiders is similar, in tune and ethereal quality, to the Diva's to call forth the chiropterans from the anime series, Blood+.

When Velma looks into Grim's head the first time, you see a little scene of Betty Boop dancing with a dog.

When Grim said, "You're not scary either, Boogie," Boogie said, "I know," and he was perfectly fine with it. But in the Big Boogey Adventure, his fear is not being scary.

Boogey was younger then. He might have been perfectly fine with it Back then.

This movie is hugely similar to the season premeir of "Doctor Who"'s "The Runaway Bride". Such examples are: "Spider Queen" & "Empress of the Racnoss".
-Jeff's marriage and Donna's marriage
-The scene where Spurg is swinging from one window to another such as Donna
-The attempt of spiders to conquer Earth
-The giant webs with captured people

Also amusing is that the Grim movie ended just as "Doctor Who"'s season premair began that day.

The Flintstones:

The town Grim was playing in seems similar to Bedrock from The Flintstones.

When Grim`s memoirs were shown, he had a full head but before that, Velma Green the Spider Queen had eaten the top of his head.

Milk Carton Cow: I can feel the hate flow through you.

That is a direct line from Emperor Palpatine from Star Wars Episode VI: Return of the Jedi.

Spider-Man 3
There is an obvious note to the use of spiders in this episode. But as seen in the commercial, it uses the Spider-Man 3 font. This shows that it is actually trying to relate to Spider-Man, and possibly use it to draw in viewers.