I had a conversation a few weeks ago with Tristam and some other people about direction finding in terms of car navigation systems, and how I felt it reduced to a weighted directed graph and that it should be possible to build from a large enough set of GPS logs. There was general agreement that this wasn't unreasonable. This prompted me to actually see what was out there, which led me to OpenStreetMap, who have been going for over a year now and see to have a reasonable number of people involved.

They lack any data around Norwich however, so I thought I'd see what I could do to remedy that. I bought a basic USB GPS device, hooked it up to my laptop, installed gpsd and gpsdrive and went for a test drive. gpsdrive seemed to be doing the right thing, with the track it drew matching up with the map being displayed. However when I uploaded it to OSM it seems to be out by a reasonably constant factor. This has led me into the tricky world of GPS datums and hoping that that's what at fault rather than it being the fact I bought a cheap Haicom Hi-202 rather than something more expensive. quinophex has a Garmin however, so he's going to lend it to me so I can run the 2 side by side and see what happens. It'd be really nice if I discovered it's just a conversion thing and that the tracks I got of a trip to and from Redbus could still be imported...

Anyway, if you do GPS stuff at all I'd highly recommend uploading some tracks of your local area and even potentially doing some markup of nodes and streets; if everybody just did a little bit local to them and perhaps a few longer journeys then things should start to get linked up and filled out, which would increase the appeal a lot.