When Hamm is flipping through the channels, you can see a portion of 'Luxo Jr', a short film from Pixar, featuring  the Pixar Lamp.

One of the biggest in jokes is for Linux users - note the penguin at the end (ie. the Linux logo, complete with red bow tie), singing "you've got a friend in me", in a computer generated film....

More tributes and references to Star Wars: at the beginning of the movie the sound of the laser gun in Buzz's arm is the sound of a Star Wars blaster. Also the sound of the hologram of Zurg's energy source (a battery) is the sound of a light saber.

When we first meet Mrs. Potato Head, if you pause the movie, you can see that she's reading "A Bug's Life".

At practically at the end of the movie when Bo Peep is admiring Woody's fixed arm, if you look in the picture on the calendar in the background it is one of the early pictures of A Bug's Life (shows A Bug's Life type ants carrying food across a leaf).

In the beginning of the movie when Buzz is on the moon land looking for Zurg the moon land background is Ant Island from A Bug's Life only in a different colour.

Sid's sister Hannah can be seen in the airport when the toys go across the floor in a pet cage. She is with her back to the camera playing with another kid in a black chair.

Sid's red tool-box and yellow alarm clock (from the first movie) can be seen when Woody hides behind a giant yellow pepper-shaker at the yard-sale.

For us Brits: The baggage handler that says "There's a couple more bags coming from the Terminal" is children's TV presenter Andi Peters.

Various movie references. The line from Empire Strikes Back - "I am your father". Also, the automobile three-point turn when the toys are in Al's Toy Barn, coming from Austin Powers. Not to mention the Jurassic Park shot of a T-Rex chasing a car viewed from the side mirror. A tribute to Mission Impossible when the slinky dog reaches in to try to open the case containing Woody. The opening seemed like a tribute to Starship Troopers - voyage, landing, survey, and sudden surrounding by aliens. The eye-on-a-stalk that followed soon after resembled the scene at the entrance of Jabba the Hutt's palace. Stinky Pete says a very familiar line - "Turn me around, so I can see", said by C3PO when he's in bits on Chewie's back. Yet another Star Wars tribute, the aliens tell Buzz to use the staff of power, referring to the gear shaft, much like "Use The Force, Luke." Buzz's breathing in his suit at the beginning in like Darth Vader. When they are about to cross the street the slinky dog says "I'm not a smart dog, but I know what Roadkill is" which is from Forrest Gump when he says "I'm not a smart man but I know what love is". The eye on the stalk before Buzz goes into Zurg's base is a reference to HAL from 2001: A Space Odyssey. Mr. Potato Head throwing his hat like Odd Job from Goldfinger. The Prospector being scared by flashbulbs was from the Hitchcock film Rear Window. Doesn't the feather falling in front of Buzz when he falls off the back of the car kidnapping Woody bring to mind "Forest Gump"?