An early pitch for the story that became "Future Tense" had the USS Defiant (from The Tholian Web (1968)) appearing instead of a timeship from the 31st century. The Defiant later appeared in In a Mirror, Darkly (2005) and In a Mirror, Darkly, Part II (2005).
Among the images in "Daniels' database" is a news article on President George W. Bush's State of the Union Address for 2003.
This episode inspired several missions in the MMORPG Star Trek Online (2010) which developed a backstory for how the pod ended up in 2152 and why the Tholians were so interested in it.
While looking at the Daniels Database, Archer and T'Pol talk about the possibility of a Vulcan and a human having a child. At one point, Archer playfully asked if the child would have pointy ears. The answer turned out to be yes, as Star Trek (1966) series regular Spock was half human and half Vulcan, and had the trademark pointy Vulcan ears.
This episode marks the first appearance of the Tholians since their introduction in The Tholian Web (1968) 35 years earlier.