These are all 3.0-3.5 Edition, as far as I know.
SHADOW WEAVE
Pernicious Magic
Prerequisites: Shadow Weave Magic
Description: You can use the Shadow Weave to make your spells harder for Weave users to counter. Any creature using a spell, spell-like ability, or magic item without the Shadow Weave Magic feat is considered to be a Weave user.
Found In: Forgotten Realms Campaign
Insidious Magic
Prerequisites: Shadow Weave Magic
Description: You can use the Shadow Weave to make your spells harder for Weave users to detect. All creatures employing spells or spell-like abilities are considered to be Weave users unless they possess the Shadow Weave Magic feat.
Found In: Forgotten Realms Campaign
Tenacious Magic
Prerequisites: Shadow Weave Magic
Description: You can use the Shadow Weave to make your spells harder for Weave users to dispel. Any magic-wielding creature without the Shadow Weave Magic feat is considered a Weave user.
Found In: Forgotten Realms Campaign
http://www.dndepicenter.com/ThirdEdition/Feats/
There are also -anti- Shadow Weave feats.
Shadow Weave Metamagic Feats
Shadow Weave Metamagic Feats
"We could kill /everyone/."