Importing from Mail into Keep It

Using Drag and Drop

You can drag and drop messages from Mail to Keep It, and it will import them as standalone email message files that can be viewed in Keep It, with Quick Look, and other apps.

Using the Services Menu

To import messages into Keep It without leaving Mail, you can install an Automator workflow, and optionally set a shortcut key to activate the workflow.

See here for instructions on how to install the workflow:

Mail Import Automator Workflow

Using Mail Rules

While Keep It has no server where you could send it messages, you can accomplish the same thing using Mail rules. See here for instructions:

Mail Scripts for Keep It