Vivaldi - Summer, 3rd movement
http://www.youtube.com/watch?v=YuF4oYRktcA I can listen to this any time of the day... I'll enter for Anachronox, thanks!
...
Damn, now I'm gonna spend at least 30 minutes listening to music on Youtube. I should go to bed!
This wonderful composition (Nightclub 1960, Piazzolla) gets a special mention because I actually practice it together with my sister:
http://www.youtube.com/watch?v=U5zik9dA-bY Oh, and this, because it is awesome as well (but I gave up on it after a while; Las Abejas (the bees) from Barrios):
http://www.youtube.com/watch?v=WaFHi6GuSVI. And one last mention: Smetana - Ma Vlast
http://www.youtube.com/watch?v=kdtLuyWuPDs edit: Since Poets of the Fall have already been mentioned: Carnival of Rust is great as well,
http://www.youtube.com/watch?v=MKk1u5RMTn4