I've heard about simple addons that can send auto raid invites to anyone who whispers me a key word. Does anyone have experience with such addons and have a nice simple one to recommend?

I often lead wpvp groups on my server and it would an awesome thing to have. Ideally I like an addon with only this auto-invite feature, rather than it being part of a larger addon with features I don't need or any UI widgets getting in the way. Something simple that just runs behind the scenes would be perfect. Thanks for the advice!