Exhaled Immunity( Races of the Dragon, p. 102)
You can use your breath weapon to grant a willing creature immunity to energy.
breath weapon, Dragonblood subtype,
When you use your breath weapon, instead of producing its normal effect, you can choose to grant one willing creature adjacent to you immunity to the energy type of your breath weapon. If your breath weapon doesn't deal energy damage, this feat grants immunity to fire. This immunity lasts for 1d4 rounds. You can't use this feat on yourself.