30 Rock

When you watch out the rear window Kenneth's cousin is straight behind the car, but when the camera changes he is almost along side of it.

When Kenneth`s cousin is standing in the door his hand is outside the door frame, but when the camera changes side his hand is inside the frame.

The trucker hats Frank wears in this episode read "Force Field" and "Alien Knight Force".

The trucker hat Frank wears in this episode reads "Alabama Legsweep".

The trucker hats that Frank wears during the episode say "Mystery Solver" and "Bahama Trapezoid".

The trucker hats Frank wears in this episode read "Mash Potatos", "Beef Ravioli" and "Atomic Super Kick".

The trucker hats Frank wears in this episode reads "Doppel Ganger" and "Liz Rocks".

Kenneth mentions trying the Donaghy Estates sparkling wine, despite the fact that Kenneth does not consciously drink alcohol because of his religion.

The trucker hats Frank wears in this episode read "Coool As Ice" and "Time Travel Agent".

Frank's trucker hat in this episode reads "Squeeze It".

The MSNBC news crawl in this episode uses some ridiculous headlines:

"Panda Murder-Suicide Shocks China"
"Wolf Blitzer Injured In Wolf Blitz"
"Mysterious Visitor From Future Wins Lottery Again"
"Anne Heche Leaves Husband For Pony"

In the opening scene an "arrow through the head" gag suddenly appears on Jenna's head.

When Liz and the Cat Wrangler are discussing the runt kitten, the kitten that Liz is holding switches from full tabby to spotted white tabby.

The trucker hats Frank wear in this episode read "1,000,000 POINTS" and "UFO Cop".

The trucker hat Frank wears in this episode reads "Extra Cheese."

Frank's trucker hat says "High Score."

The trucker hat Frank wears in this episode reads "Smells."

Kenneth can be seen cleaning off lettering on Brian Williams's wall.

The following can be seen with the rest of it scrubbed off:
KAT
COUR
SU

This can be inferred to have read "KATIE COURIC SUCKS" as a joke. Katie Couric hosted the CBS Evening News opposite Williams's NBC Nightly News at the time of the original broadcast of this episode.

The trucker hats Frank wears in this episode read "Karate Sluts" and "Beef N Bean."

When Jack is eating Kenneth's sandwich and picks up the milk, he has taken a big bite out of it, but when the camera changes angle and Jack drinks the milk the sandwich is whole again.