Try searching for Maemo Mapper by Gnuite. Quite a handy little app. Allows you to download several different map types (google, virtual earth,etc.) at various zoom levels directly to an internal repository for offline viewing. What's better is that if you have a bluetooth GPS reciever you can use it as a navigation tool with spoken directions (sounds like Stephen Hawking guiding your journey) and *most* everything else coming from a dedicated navigation device.