Weapon
In the Norse myths, Thor's weapon is a hammer called Mjöllnir. The anime gives the weapon a more Japanese twist by making it a wooden sword instead. Mjöllnir was always important to Thor in the myths and in the anime, Thor often refers to it as his “trusted partner.”
Myth/Anime Storyline Parallels
At one point in the original myths, a giant steals the weapon Mjöllnir (mentioned above) from Thor. The giant then refuses to give it back unless Freyja (the goddess of love, beauty, and fertility) agrees to marry him. She refuses to go however, and the other gods form an alternate plan to get the hammer back. Thor, though vehemently opposed to the idea, was forced to put on a bridal gown and veil. He then goes to the giant, pretending to be Freyja, playing along until the opportunity arises to recover the hammer.
The anime pays homage to this story in one episode where a character is getting married, but winds up kidnapped by the antagonists. The bridesmaid, not wanting the guests to get impatient, convinces Thor to dress up in the white dress, veil, and make-up of the bride for the first part of the ceremony. (Not realizing the emergency, Thor and the bridesmaid hoped the real bride would still come.)
[Okay, this is the last subject I'm talking about on the Norse Mythology vein. With the Norns, Loki's children, Freyja and Freyr, Heimdall, the concept of 'Ragnarok,' not to mention all the monsters and deities that made cameo appearances in different episodes, I could probably go on about this forever...]