I've set out to map my home town, Foster City, and use it as a means to create a better tutorial for data collection and editing.

The city has a fair number of attributes that make it a suitable crucible, including pedestrian/bike paths, undivided residential streets that suddenly change names or become divided, lagoons, parks, bridges, coastline (SF Bay), and a state highway that runs through it.

First tip: Setting my GPS tracklog to capture every 2 seconds seems to work well for capturing just the right amount of detail. It's just barely enough, for instance, to create a slight knot in the track at stop signs (so long as you're not making a California stop!), to aid in determining where to place a point in the intersections.