Whether you work quietly alone at home or in an office where the hum of fluorescent lights is the dominant soundtrack of your day, tune into one of the 31 ambient loops offered on the iSerenity web site. Listen to the clack of typewriters and maybe your own keyboard pace will pick up; if you miss the big city, you can have New York City as your background (at least, the safe-for-work version); expatriate Angelenos would probably prefer “Highway Hiatus.” It’s like selective serotonin reuptake inhibitors for your ears. Looking for more phonic tonics? SimplyNoise does white noise in your browser and does it well. Serenity now.