Here's a world map I've been working on - it's for a fantasy novel I'm planning to write some day. Or maybe turn into a RPG campaign setting, I don't know.
I've used Photoshop to create the shape of the world, and imported that as vector shapes into Illustrator. Here's what I've done so far:
I imported the thing into Photoshop and played around with mountains and jungles - these are just some preliminary sketches:
And here I've overlayed a world map to give you an idea how big it is, it's not 100% accurate though.