From the Grimnismal (Poetic Edda): "Oer the whole world wide, every day, fly Huginn and Muninn. I worry lest Huginn should fall in flight, yet more I fear for Muninn." Gather round, ye lunatic fringe...Odin had two ravens, Huginn [Thought] and Muninn [Memory], that flew over Midgaard every morning and returned each night to inform …
Odin's Other Eye 