I got myself a Nokia 770 last summer and been using the most excellent maemo-mapper to navigate around Finland. I'm mostly very happy with it but route planning and place search is something I would really like to have (and for free that is). The biggest problem is that there is no free map data available (for €€€ you can always get the digiroad data but that is not an option).
On my quest to find map data I found out about the OpenStreetMap project. And since couple of months been eagerly adding as much data as I can gather when I drive around. It's not loong ago when Turku was almost empty, but now it's starting to look like a map. I think I'm mostly alone in Turku, but someone is working around Tampere and Helsinki. But we would really need more people involved.
There is still a lot of work to do but