For classicals I find light-hearted sonatas and chamber music good for concentration. Symphonies are usually too distracting. Other times I like the "ambient"

For classicals I find light-hearted sonatas and chamber music good for concentration. Symphonies are usually too distracting. Other times I like the "ambient" channel on www.pandora.com. A while ago when I was hooked on Flight Simulator I had a Boeing 747 running in the background while I worked. The engine sound + distant radio chatters produce a calm atmosphere.