In Norse mythology, Sindri (from the old Norse word "sindr", meaning "spark") was the name of the dwarf who fashioned Thor's magical hammer, Mjolnir. Mjolnir was a powerful weapon, and was vitally important to the Æsir, or Norse gods. Once it was stolen by the frost giant (or troll, in later texts) Thrym. This was viewed as a potential disaster by all of the
Æsir because it left them virtually defenseless. Worse, it could have been used against them by the frost giants.
Loki, the god of mischief, persuaded Thrym to return Mjolnir to Thor if Freya (the godess of love) would agree to be his bride. Freya was understandably horrified at the prospect of becoming the bride of a troll, and refused. Loki then presented Plan "B" to Thor: Thor would disguise himself as Freya, and (wearing a veil) would accompany Loki to the land of the frost giants for the wedding.
Thrym receive Loki and the disguised Thor without suspicion, but was surprised at his bride's appetite: eight salmon, a full-grown ox and other "delicacies", washed down with a tun of mead.
Before Thrym could retire with his "bride", Loki insisted that he present "Freya" with a suitable wedding gift. Thrym, still not suspecting anything, presented "Freya" with Mjolnir. By this time, Thor, having been dressed as a godess for a considerable period of time, removed his disguise and used Mjolnir to slaughter Thrym and the rest of the trolls. Some believe that this was the origin of the maxim "If all you have is a hammer, everything looks like a troll."
