The documentation for the original release of Space Quest V is the Galactic Enquirer, a parody of an actual tabloid called the National Enquirer.
When you need to rescue Cliffy near Thrakus; waste all the fuel of your EVA pod before you get him. You'll get caught by the planet's gravity and crash. The camera shifts towards the surface of Thrakus and shows two mushrooms have a conversation as they watch Roger come down:
Mushroom # 1: "Ah look, Crumpella a shooting star. Make a wish."
Mushroom # 2: "Ok. Slep. I wish... I wish... I wish I had never bought Rexx Nebular."
I guess Sierra didn't like Microprose's Space Quest rip-off Rex Nebular and The Cosmic Gender Bender :->
Worf from Star Trek is sitting in the academy's classroom. However, he has been renamed "Woof" and is described as the academy's ambu-jitsu champion.
Elvis appears in the right half of the academy rotunda.
Darth Vader and Obi-Wan Kenobi are fighting their famous lightsabre battle in the academy hallway.
In the academy's landing bay, there's a skull fighter from SQ3.
The guards in the rotunda are playing games on their consoles. Specifically, they're playing "Asteroids" and "Missile Command".
In the Eureka's shuttle lab, there's a display above the teleporter. The computer is playing an old (REAL old) game called Pong on it.
The moon visible through the academy's rotunda windows is described as "one of the nine moons of Nova", in reference to the Dynamix game Nova 9.
The coordinates to Klorox are 90210 - the same as in that ridicilous TV show.
The Tasmanian devil is in one of the cages at Genetix (then again, it might be the Labion Terror Beast from SQ2).
The Astro Chicken from Space Quest 3 has a quick appearance in the Eureka's pod bay. There's a row of lockers to the far left. Open the leftmost one and watch!
The PacMan makes a quick appearance in the Goliath's ventilation system. On level 8, find the intersection where you can go in all four directions. Go left. Roger will come back, followed by the PacMan.
Both Flash Gordon and Albert Einstein are mentioned on the academy's grade machine. They both fail, too.
The Millenium Falcon is disguised as the bridge simulator (check it out when Roger walks away from the sim). Captain Quirk has a Dynamix coffee cup. It's visible when the Eureka intercepts the strange transmission.
Space Quest 5 is the second Sierra adventure game to feature product placement by the US-American telephone company Sprint. The first game was Leisure Suit Larry 5. Instead of text messages like in Larry 5, this time Sprint paid for graphic advertisement. The Sprint logo would end any communication transmissions, as well as appear on a billboard in the Space bar. See the screenshot section for examples.
This was the first Space Quest not created by both of the Two Guys From Andromeda (Scott Murphy and Mark Crowe). After Space Quest IV, the two guys split up as they need a change of climate and didn't want to be remembered solely for their Space Quest games. Mark Crowe would later go on to design Space Quest V solo.
Unlike the other five Space Quests, this one was in fact programmed by Dynamix (since Mark Crowe, the guy formerly from Andromeda, was working there at the time). The Dynamix logo appears at least twice throughout the game, and in one scene a couple of the motion capture aliens are wearing spare costumes taken from the set of Betrayal at Krondor.