You can generate a field of silence more often than other whisper gnomes can.
Prerequisite: Whisper gnome.
Benefit: You can use your racial silence spell-like ability a number of times per day equal to 3 + your Charisma bonus. Normal: A whisper gnome can normally use his silence spell-like ability once per day.
Special: You can take this feat more than once. Each time you take it after the first, you gain three additional uses of your silence ability per day.
Source: Races of Stone, page 139.