Akonadi - The PIM Storage Service.

Intends to design an extensible cross-desktop storage service for PIM data and meta data providing concurrent read, write, and query access. It will provide unique desktop wide object identification and retrieval.

This logo tries express the way akonadi architecture is built around a central storage which is accessed through a language and platform.
Akonadi is designed to be accessible to a broad range of applications and resource implementations. It’s part of the concept that it’s easy to add additional APIs and users of the APIs.