"The Nutcracker" is up on my favorite music list.  The original story that it is adapted from is much darker.  The ballet we know is very Chrismas, but I think astral travel should count. 

Hoffmann's story was originally published in 1816 as part of a collection of children's fairy tales (titled Kindermarchen) with a decidedly dark side. Where the first act story of the ballet leaves off, Hoffmann continues with the story of many digressions and multiple transformations. Princess Pirlipat is transformed to a hideous dwarf that can only be restored by someone cracking the incredibly hard Krakatuk nut. None other than Drosselmeyer’s nephew can perform this trick. When it looks like a happy ending Drosselmeyer once again upsets Dame Mouserink and another evil spell is cast. It can only be broken by killing the seven headed Mouse King. The Nutcracker eventually is triumphant over the Mouse King and sails off with Marie through various enchanted places to arrive eventually at the Marzipan Castle. Some years later Marie encounters Drosselmeyer’s nephew in real life thus placing a shadow on the line between myth and reality. Hoffmann bases the Stahlbaums on the family of a Berlin publisher, Julius Hitwig and the character of Drosselmeyer on himself. The Stahlbaum's children are Fritz, Marie and older sister Louise. Clara is one of Marie's dolls who is asked to give up her bed for the injured nutcracker. The Dumas version is much sweeter than the original Hoffmann.

http://www.balletmet.org/Notes/NutHist.html