OST from Journey, Uncharted, Legend of Korra are always good options. Also Goldberg Variations by J.S. Bach keeps me focused.

I spent the days preparing an oral exam in high school listening to Nyan Cat. It kept me working and focused most of the time, and I ended up with an A..
However, I wouldn't really recommend it...

While while while, please check your grammar, or are you trying to fool us? :l