Space Quest/YMMV

General

 * Ear Worm:
 * The theme tune, which crops up in at least a dozen variants throughout the series.
 * The Skate-O-Rama theme will drive you mad haunting your brain. It's the perfect combination of catchy, repetitive, and really annoying.

Space Quest I

 * Padding: The gambling minigame is a blatant example, likely taking up at least a third of the time it takes to beat the game.

Space Quest III

 * Awesome Music: One of the first Sierra games to actually make use of either AdLib or Roland MT-32, and while it was still merely EGA with 16 colors, it made the experience far better than the plain Internal PC Speaker which was the norm until then.

Space Quest IV

 * That One Level: The Skate-O-Rama scene where you have to escape the sequel police. Maneuvering is not only difficult, you also have to avoid getting shot!

Space Quest V

 * That One Level: Finding and rescuing Cliffy with the EVA pod. Not only you need to locate him first, you must do it quickly before you run out of fuel and oxygen. And don't forget that you also need to return to the Eureka. Made more frustrating with the infamous Sierra speed bug that make the oxygen and fuel depletion exaggeratedly faster.

Space Quest VI

 * Harsher in Hindsight: The narrator makes several snarky comments about the viability of another Space Quest game... Umm... Yeah... About that...
 * Hilarious in Hindsight: Stooge Fighter III is a parody of Street Fighter II. The actual Street Fighter III would show up two years after this game's release.
 * Squick: How does Roger escape Stellar's body? Why, no other than by flashing his ship's headlight through a large zit on her nose, which then gets popped so that Roger shoots out in a dollop of pus.