Eye-Fi is at it again with a new Wi-Fi memory card that not only lets you wirelessly transfer images from your camera to your computer, as well as an array of online photo sharing services, it also enables “place-stamping” of your photos. Now you can track, with startling accuracy, where you snapped every photo. This, of course, is not always a good thing, but I assume you can turn the feature off…

There’s just one catch; the card doesn’t use GPS technology. Instead, it relies on all those Wi-Fi signals floating through the air to triangulate your position (and no, you don’t have to be actually connected to a network. Just a signal is enough). This is great if you’re in a populated area with Wi-Fi all around. It won’t work when you’re snapping pics on your hike up to Machu Picchu.

Even so, says David Pogue of the NYT, the card can successfully add a location stamp to your photos in “70 percent of the populated areas in the United States.” Not bad.

More on this from David Pogue (who else?).