The National Map is a great example of government serving the people. In my quest to better characterize my bike trips, I wanted to figure out how steep the hills were leading up to my apartment. I did some quick searches on the web, but all I could find was poorly scanned images of topographic maps or maps for which you had to pay.
I had finally resigned myself to purchasing a map, thought I’d go to the US Geological Survey and see if I could purchase it directly from them. After a few clicks, I found The National Map, which is a compendium of most of the topographic data the USGS has on the US. You can overlay features, click between two points and get the difference in distance and altitute and all kinds of other great information. Found out I regularly bike a 5% grade to/from work (The Highwood Hill) which, at times, exceeds 8%. Found out, over my entire trip to/from work I actually go down about 50 ft, which helps explain why it always felt like I went up more hills in the evening than I did in the morning!