The main advantage of cell phone tethering is the ability to get more mileage out of a single 3G subscription. The tethered host treats the linked 3G phone as a modem, using dial-up networking or a carrier-supplied wireless connection manager to initiate calls to the carrier’s network. Depending on your phone and laptop, those two devices may be apple iphones linked using Bluetooth, Infrared , USB cable or serial cable. Alternatively, a mobile worker who has already purchased a 3G phone, or who expects to do so in the near future, should consider tethering that phone to his or her laptop.