Lately, I've been finding some home theater enthusiast as well as some audiophiles taking advantage of the 240 volts of balanced power available in every American home. Most equipment today is capable of running at 240 volts. If it uses a linear supply, it usually has two taps on the transformer and a voltage switch somewhere on the unit. The switch can be set to 115 volts or 230 volts (+/- 10%). If it has a switching power supply, it can utilize anything from 90 to 250 volts without making any changes.
Most amplifiers will actually output a little more power when connected to 240 volts. This is highly recommended for large mono blocks and subwoofers. Since the power is balanced, it also has a lower noise floor. Anyone who is running a dedicated line might want to consider this.
Some audiophile grade isolation transformers can also be configured for 240 volts in and 120 volts out. Then you can keep any power conditioners, distribution strips, and power cables you already have and still take advantage of the 240 volts available in your house.