"The Theft of Thor's Hammer" is one of only two stories in which Freyja's magical feather dress makes an appearance. Loki borrows it one other time in the story of Thjazi.
Most critics agree that the story of the theft of Thor's hammer, "Thrymskvitha," was composed around 900 A.D. (source).
Comic book creator Stan Lee, who created the "Thor" series for Marvel Comics, explains that he liked the idea of Thor as a superhero because readers weren't as familiar with the Norse gods as compared to the Greco-Roman gods, and because "I pictured Norse gods looking like the Vikings of old, with the flowing beards, horned helmets, and battle clubs" (source).
British clothing line Motel has created a dress with a graphic feather pattern they call the "Freya Dress" (source).
Although the origin of the word "Mjollnir" (the name of Thor's hammer) is uncertain, it's probably related to the Old Norse word mala ("grind") or molva ("crush") with possible cognates in Russian (molnija) and Welsh mellt, both words for lightning (source).
Until the turn of the century, Danish people referred to stone axes and fossils they found and kept as charms against disaster as "thunder-stones" or "thunder-weapons" (source).
To play Loki in the Thor movie (2011), actor Tom Hiddleston had to go on a strict diet because "physically, [Loki] can't be posing as Thor" (source).
Beowulf mentions Freyja's necklace, Brisingamen, as a way to describe how amazing the necklace is that Wealhtheow gives Beowulf (source: Beowulf 1199).