Some time ago, I came across a website that showed two maps side-by-side, so you could compare the latitude and longitude of points you dropped on the map. See, I'm a huge appreciator of Japan, and have dreams of travelling there one day. I was reading an article about how rare snow was in Tokyo, and it didn't quite register in my head how that made sense. I knew Japan's archipelago was large enough that it spanned almost the length of the US West coast, but I thought it was centered around the same latitude as where I live (upstate NY). Boy, was I wrong!
Embarrassingly, I'm actually not that great with geography, so my concept of where exactly Japan lined up wasn't anywhere close to correct, but MAPfrappe showed me that Tokyo is actually at the same latitude as North Carolina. Snow in Tokyo is about the same phenomenon as snow in Charlotte (if you're not from the US, a dusting of snow is enough to shut Charlotte down for a few days)! I was happy to find the site and see where else in the world correlated to my own area - I probably wasted a few hours just dropping pins in places to see where things lined up; and now I know when I finally make my way to Japan, I want to visit Hokkaido too, since it's my latitude sibling. :)
What revelations have maps shown you in your work (or even off work) hours? Is there another tool like this one that you know of that could show us other parallels around the globe?