Music affects me in different ways. Music such as Coldplay, Snow Patrol, Keane and so forth relaxes me, it soothes my spirit so to speak.
Music such as Red, Breaking Benjamin, Evanescence, etc. often encourages my more creative side in the fantasy/sci-fi aspect, often encourages me to write.
Trance/House/Electronica (whatever you want to call it) can spark that same creative side but in a slightly different way I suppose. Often it's a mixture of the top two answers of mine.
Country music and rap music have the same affect on me and that would be a feeling of being hyper or funny. I get energized, the thing with these genres are is that I get bored with them very fast.