Flight of the Bumblebee

"Flight of the Bumblebee" is an orchestral interlude written by Nikolai Rimsky-Korsakov for his opera The Tale of Tsar Saltan, composed in 1899–1900. The piece closes Act III, Tableau 1, during the magic Swan-Bird changes Prince Gvidon Saltanovich (the Tsar's son) into an insect so that he can fly away to visit his father (who does not know that he is alive). Although in the opera the Swan-Bird sings during the first part of the "Flight", her vocal line is melodically uninvolved and easily omitted; this feature, combined with the fact that the number decisively closes the scene, made easy extraction as an orchestral concert piece possible
Although the "Flight" does not have a title in the score of the opera, its common English title translates like the Russian one (Полёт шмеля = Polyot shmelya). Incidentally, this piece does not constitute one of the movements of the orchestral suite that the composer derived from the opera for concerts.
Those familiar with the opera Tsar Saltan may recognize two leitmotifs used in the Flight, both of which are associated with Prince Gvidon from earlier in the opera. These are illustrated here in musical notation:
The music of this number recurs in modified form during the ensuing tableau (Act III, Tableau 2), at the points when the Bumblebee appears during the scene: it stings the two evil sisters on the brow, blinds Babarikha (the instigator of the plot to trick Saltan at the beginning into sending his wife away), and in general causes havoc at the end of the tableau. Readers of Aleksandr Pushkin's original poem upon which this opera is based will note that Gvidon is supposed to go on three separate trips to Saltan's kingdom, each of which requires a transformation into a different insect.
"Flight of the Bumblebee" is recognizable for its frantic pace when played up to tempo, with nearly uninterrupted runs of chromatic sixteenth notes. It is not so much the pitch or range of the notes that are played that challenges the musician, but simply the musician's ability to move to them quickly enough.
Although the original orchestral version mercifully assigns portions of the sixteenth-note runs to various instruments in tandem, in the century since its composition the piece has become a standard showcase for solo instrumental virtuosity, whether on the original violin or on practically any other melodic instrument.

http://www.youtube.com/watch?v=-gfP-ag6i5o