AfterLogic XMail Server is an email server. It supports ESMTP, TLS/SSL secure connections, SMTP authentication, account and domain aliasing, anti-spam features (IP-based and email address based), mailing lists, logging, remote administration, the Finger protocol, filters, and custom mail processing. AfterLogic XMail Server is based on the XMail server, but features simultaneous multi-user access to a POP3 mailbox, the ability to configure port numbers via a configuration file, a Windows installer, and a Web administration tool with an AJAX interface.
Arachne is program that implements Avidan and Shamir's seam carving technique for content-aware image resizing. It allows realtime, fluid image resizing using this fascinating technique. Seam carving works by removing the "boring bits" from an image, so it can change the aspect ratio of many images without changing the shape of the objects inside.
Artha is a handy thesaurus based on WordNet with distinct features like global hot key look up, passive desktop notification, regular expression based search, etc. Artha may be used as a free open-source replacement/clone to the proprietary WordWeb Pro thesaurus (which is also based on WordNet) on Unix-like and Windows operating systems.