It kills me that people still believe this.
Discharging a battery to 0% will use up a charge cycle. Modern lithium-ion and lithium polymer batteries do not suffer from memory problems the way that older nickle-based technology did. Instead, modern batteries are much like modern "smart" inkjet printer cartridges - there's an onboard EEPROM that monitors the number of charge cycles on the battery. Any time the battery goes to 0% and is recharged, that's a charge cycle. There's a set number of charge cycles allowed on a battery (similar to how there's a set number of uses on an inkjet cartridge, and the cartridge notifies the printer when its ROM says it's all used up). OEM battery utilities from HP, Apple, and others simply look at the number of charge cycles on the battery.
Once the battery's charge cycles have maxed out, the battery doesn't work anymore - it will tell the OS it's consumed, and prevent the computer from charging it. This is a safety mechanism to prevent batteries from expanding, exploding, and/or catching fire.
By "calibrating" a lithium-based battery, you're effectively shortening its lifespan. If you do it frequently enough, you'll ruin the battery.