The film's setting is an archaeological dig at "Olduvai" on Mars. Earth's Olduvai Gorge contains some of the earliest human and hominid (pre-human) remains and artifacts. This was the setting for the opening scenes of 2001: A Space Odyssey (1968).
The names of scientists Dr. Todd Carmack and Dr. Willits are references to Todd Hollenshead, John Carmack and Tim Willits, co-owners of id Software, and developers of the Doom game and its sequels, including Doom³ (2004) upon which this movie is based.
When Sarge uses the severed hand to open the advanced weapons armory, the computer voice (and subtitles) say, "Welcome, Dr. Patricia Tallman." The character is named in the credits as Dr. Hillary Tallman. Much like the inclusion of John Carmack's name, this is a subtle insider reference, but one that is arguably more likely to be noticed than the name of ID Software's infamous co-founder Carmack.
During the end credits, a remixed version of the song "You Know What You Are" by Nine Inch Nails plays. Trent Reznor, NIN frontman, headed up the music and sound design for Quake (1996), which was also created by id Software.