You could have downloaded dasco 3.0 for Mac from our application library for free. The program is categorized as Communication Tools. This free Mac app is an intellectual property of DonorWare LLC.
From the developer:
dasco is designed to provide non-profit organizations with effective donor communication, personalized receipting, efficient donor accounting and constructive analysis of fund-raising efforts. The app provides virtually limitless profiling of donors: special lists, flags, supplemental, "turbo" profiling all allow you to not only track a donor's profile, but to communicate with them according to their interests and preferences.
You may want to check out more software for Mac, such as Mailplane, SpamSieve or MailRaider, which might be similar to dasco.