Warning: This is 3.0 Edition material. It is possible that there is more recent 3.5 Edition version.
Inaccurate?

Rapid Breath

( Savage Species, p. 39)

[Monster]

You do not have to wait as long to reuse your breath weapon as you normally would.

Prerequisite

Breath weapon, Quicken Spell or Quicken Spell-Like Ability,

Benefit

The required interval between uses of your breath weapon is reduced by 1 round. For instance, a dragon with this feat can use its breath weapon once every 1d4-1 rounds instead of every 1d4 rounds. If the 1d4-1 result is 0, the dragon can breathe again in the following round (but not twice in the same round). If the interval is a fixed period of time, such as once per hour, the interval is halved.

Special

If you have multiple heads with breath weapons, all your breath weapons use the new interval.