In one of the more practical developments to emerge from Washington, the U.S. Geological Survey has come up with a new generation of topos that let you customize your terrain. Digital and downloadable for free, the maps have layers of geographic data in PDF format that can be switched on or off, depending on how much topographic info you really need. And yes, you can do mash-ups with Google Maps and print to scale.
For map buffs, this is like buy-one-get-a-dozen at the local donut shop. It's not for dial-up connections -- the average quadrangle download runs about 16 megs -- and you might need to download some additional plug-ins to run all the electronic analysis tools available. And no, the whole country isn't available yet. Colorado's super-variable topography is still being processed and won't be available until next year.
But for a glimpse of the possibilities, check out the National Map Project at the USGS site; for more on current maps and features, go here. And for Denver's own role in the mapping revolution, see our 2006 feature "Caught Mapping."