VerticalReponse used to offer a 15% discount to qualified nonprofits -- and they still do.  But now, the first 10,000 e-mails you send through VR each month will be free! You can read all about in on their web site [1] and blog [2].

NTEN uses VerticalResponse for App Exchange to send out our monthly newsletter, NTEN Connect, [3] and we've been generally pleased with its performance.  I suspect the price break will only increase our level of satisfaction.