Evernote is a natural complement to OmniFocus. Use it to store ideas for upcoming projects and as a repository for project reference material.
Evernote is a cloud storage solution supported by apps on virtually every platform. These apps allow you to easily add and access data stored within your Evernote repository. Evernote notes are stored in notebooks and can contain text, images, audio, video, and even documents.
Each note in Evernote has a unique link and can be referenced from an OmniFocus project, group or action. Additionally, links to OmniFocus projects, groups and actions can be stored within Evernote notes so that you can conveniently access your OmniFocus database from your Evernote notes.
Tip: Use the TaskClone service to automatically create OmniFocus actions from to-do checkboxes in Evernote.