I recently stumbled across the excellent 'Magnificent Maps' blog run by the British Library.
I'm a massive fan of all things natural history, and these octopus maps are astonishing things, coincidentally tying in with some work I'm busy producing myself.
As the blog post discusses, the octopus was increasingly used in political and satirical maps and illustrations, with the creature's groping tentacles perfectly descriping the total domination plans of the power-hungry.
There's a great BBC Four short clip on iplayer here showing one of the devices earliest uses, in Fred Rose's map of Russia reaching out to spread across Europe.
Update... not massively related, but here's a cool Max Ernst Octopus thing! YES!