You could have downloaded FastMailBase 1.1 for Mac from our software library for free. The program belongs to Communication Tools. The actual developer of this Mac application is ManyBases.
From the developer:
FastMailBase purpose is to bring you an easy and elegant way of archiving, retrieving and organizing all your emails.
Until now, people making intensive use of personal or professional emails exchanges had no other choice than simply keeping them in their mail application, by organizing them in folders and subfolders.
You may want to check out more software for Mac, such as Enough, MailBrew or Seesmic for Facebook, which might be similar to FastMailBase.