When Greg crashes his Bug into a utility pole, the sound effects are that of a radiator hissing and the engine stalling. The engine to a VW bug is located in the back of the car, the front is merely a trunk of sorts.
When Clark, Chloe, and Pete are investigating Greg's house, why is there steam coming from the bathroom? There was no water running in the shower and there were no sounds of any water running when they were in the bathroom.
After Greg hits Clark with the pipe in the foundry, Clark's hands are very dirty. In the closeup on Clark's hand immediately after he lands, the hand is clean to show the effects of the kryptonite.
Why does no one ever seem to notice that the meteor rocks (as on Lana's necklace) glow an eerie green colour whenever Clark gets anywhere near them?
When Clark is returning Lana's necklace, he obviously exposes himself to the meteor rock radiation. So, how then, can he not get sick from it (first of all), and, secondly, how can he have the strength to speed-run away from her door before she sees him?
When Lana goes to ask Whitney about what happened to Clark the night of the dance, she is wearing a denim shirt over a white shirt. After talking to Whitney, she runs down the stairs, and you can see she's wearing a light blue skirt. Then when she went to go see Clark right after, she's wearing the same denim shirt and white t-shirt combo, but black pants. If it was urgent that she talk to Clark, why'd she change?
Tom Welling's hair goes from long to short and back several times during the episode. After "Pilot," five inches were cut off of Tom's hair. When the hair continuity error was discovered, a hairdresser from L.A. was flown in to give him hair extensions.
Clark: Oh, Lex is definitely one of a kind.
Lana: Did you know you can see my house from here?
Clark: No. Really?
(he moves the telescope away from her house)
Clark: You know, we've lived a mile apart our whole lives and you've never come over.
Lana: And you're wondering what I'm doing here now.
Clark: Not that I don't enjoy the company, but yes, I was.
Craig's Mom: What the hell has gotten into you?
Craig: About two million years of intelligence and instinct.
Jonathan: Look, Clark, I'm your father. I'm supposed to have all the answers. It kills me that I don't, but you gotta have faith that we'll figure this thing out together.
Jonathan: Clark, kids just don't leap off the ceiling and attack people.
Lana: Clark, I didn't see you at the dance last night.
Clark: Oh, I was...(glares at Whitney)...I was a little tied up.
Lex: What is it about Kents and gifts? It's yours. Hand it to Lana. Tell her what happened. Trust me, once she opens it, you'll win her heart. That necklace gives you the power. All you've got to do is use. it.
Clark: Dad, something else happened to me this morning. When I woke up, I was kind of floating.
Clark: As soon as I woke up I crashed. I mean, Dad, what's happening to me?
Jonathan: I honestly don't know. As soon as you start breaking the law of gravity we're definitely in uncharted territory.
Jonathan: I don't know...(a bug kid) seems kinda out there.
Martha: This from the man who's been hiding a spaceship in the storm cellar for the last twelve years.
Lex: (to Clark) Save any lives on your way over? You keep it up and you can make a career out of it.
Lex: Kinda makes you wonder if you're with the right guy. One chucks footballs, the other helps save lives.
Clark: Chloe, I could never outgrow you. Other than vertically.
Pete: Which sucked, 'cause he had a killer tree fort his dad built in the woods.
Clark: It was okay.
Pete: Clark never liked it. He used to get sick just walking over there.
Chloe: How come?
Pete: He was afraid of heights.
Clark: I didn't believe it was structurally sound.
Lex: Clark, Whitney tied you up on a pole in the middle of a field. Even the Romans saved that for special occasions.
Deleted Scene 1- Pete is having breakfast with the Kents and telling them about what happened to the trucks during the dance (From the previous episode).
Deleted Scene 2- Jonathan discusses Clark's floating ability with Martha.
Musical guest stars: The Calling (Wherever You Go), Papa Roach (Last Resort), Lifehouse (Everything), Cake (Love You Madly - at Smallville High School, right before Clark talks to Chloe in the hallway), Aeon Spoke (Damaged), Weezer (Island In The Sun - when Clark is at The Farmer's Market), Better Than Ezra (I Do - when Whitney is driving his truck, right before Greg attacks), and Turin Brakes (Underdog (Save Me) - when we see Lana on her horse right before she talks to Lex).
Chad E Donella (Greg/"The Bug Guy") played another vaguely mentally disturbed mutant in an episode of The X-Files called "Hungry." His character's catchphrase, used several times, was, "You can't fight biology." In this episode of Smallville, Greg tells Clark, "You can't fight natural law."
Among the bug in-jokes: Greg drives a VW "bug", and the music playing right before he crashes is "Last Resort", by Papa Roach. Greg has a poster of Papa Roach in his room.
UPN/WB crossover-the ending song was "Where Ever You Will Go" by The Calling. This song was used to promote Enterprise on UPN.
DC/Milestone Media has a story like this in an issue of Kobalt #7. The villain had fly-like powers and appearance. Static of Static Shock fan appeared in the story.
The title of this episode comes from a short story by an Austrian philosopher named Franz Kafka. It is about a young man who inexplicably transforms into a large cockroach, and is then killed by his mother. Chloe even makes a comparison between Greg and Kafka after Clark explains about Greg's "Bug-Boy" condition.