Here’s a cool little Google Maps trick that I recently discovered: You can create a custom map containing specific places you visited. Used in conjunction with a GPS receiver, it’s an excellent way to record trip data for future reference or for sharing with others.

I entered the GPS coordinates I recorded during our latest trip to Mexico and Google Maps plotted them all nicely on a map:

View Cancun, November 2011 in a larger map

For some reason, when I tried to look up the coordinates in Google Maps while we were still in Mexico, I keep getting an error telling me that Google didn’t have permission to display the data, but I can pull up the coordinates just fine now that we’re back in the U.S. Something to keep in mind if you’re planning a foray into the Congo Basin.