Handy!

Worldmapper is a collection of world maps, where territories are re-sized on each map according to the subject of interest.

Of note: routes classified "Legal Trails". Older files are SID files, require plugin from LizardTech.

I found this while looking for a way of explaining the trails to Brattleboro visitors. Solveig and I had no idea of how extensive these trails were until, one day, we accidentally found ourselves on "Just For Fun" (we started at the southeastern edge)

a marker clustering add-on for google maps, with a nice API

a handy-looking toolkit for rails apps that need to play well with geographic data