It must be said that neither Amy Adams or Hank Azaria can count as "cameos." It must also be said that both of them delivered fantastic performances, stealing scenes from Ben Stiller at every opportunity. Azaria plays an ancient Egyptian prince, and his lisp was one of the best ongoing gags of the movie.
1. Jonah Hill
Though he only appears for a few minutes, Hill's scene is one of the funniest of the movie, and the first big laugh to appear. This appearance speaks well of Hill as a comedian because many would have taken this material (already slightly overdone dialogue) and gone overboard with it or at least tried to outdo Ben Stiller. Thankfully, Hill doesn't commit any of these faux paus but uses his material well. Best line: "It is not a free country! It's the United States of Don't Touch That Thing Right There in Front of You!"
2. Bill Hader
Okay, Hader as General Custer is arguably not a cameo. But he is actually given comic material, as opposed to several other established comedy actors who barely have a line, much less a joke to work with. General Custer is a minor character, but pops up several times , and manages to be funny on each appearance. Best line: "We're Americans, we don't plan, we do!"
Bill Hader was first widely seen on Saturday Night Live. From there he quickly transferred into movies with the Apatow/Goldberg camp and has been seen in Knocked Up, Superbad, and Tropic Thunder. His performances have been consistently great, and the part was deserved. His comic style is much more deadpan than recent popular comics like Ferrell and Sandler. Or, of course, Ben Stiller.
3. Mindy Kaling/Ed Helms
Kaling, who is slated to star in her own upcoming NBC comedy show, appears as a tour guide in the Smithsonian. Helms appears before Stiller even leaves New York, apparently as his assistant. Both of these very funny people are regular faces on NBC's The Office, and each of them were given exactly one joke. This is sad, but not nearly as sad as the fate of Keith Powell and Craig Robinson (30 Rock and The Office, respectively), who were each given one line and no comedy.
Best line was Kaling's: "I'm kidding, he's not a document!"
4. Darth Vader
Technically, Vader only stood there breathing, but there were a couple very funny jokes at his expense, delivered by Azaria. Vader is the reject villain along with Oscar the Grouch. Best line: "And what's with the cape, are we going to the opera?"
Runner-up in the area of silent characters: Giant Squid.
5. The Jonas Brothers
The best thing about this cameo is that the band seems to be making fun of itself a bit - they appear as miniature singing cupid statues. The brothers do not show their faces, but their singing is recognizable and they add some very credible comedy to the romance between Stiller and Adams.
