As a kid, geeky-ness was always somewhat embarrassing. As an adult there is a style to it, as though geek has gone mainstream, and gadgets have become the merit badges of chic.
Here’s one way to up your geek street cred: Outfit your car with an electroluminescent bumper sticker that indicates the presence and strength of a WiFi network.
This isn’t just a decal, it’s a decal that lights up, and the stronger the WiFi signal in your immediate vicinity, the more bars this gadget displays. In this Instructable you’ll find that the electronics and display actually came from a T-shirt, and a little googling will show that there are all kinds of WiFi detecting T-shirts and hats out there, plus ones with graphic equalizer displays that react to sounds, and dancing smiley faces.
In this Instructable the author detaches the decal from the T-shirt and hacks up a car cell phone charger to remove the 12V to 5V power supply. The power supply goes into the battery case that comes with the decal (to power the decal in place of the batteries), and is in turn hard wired into the parking light circuit so the decal comes on whenever the lights are turned on. It’s not bright enough to bother with during the day.
The decal itself is taped to the inside of the hatchback glass, so not technically a bumper sticker, I suppose.
While I like the bumper sticker idea, I think I like the T-shirt better. Google them and decide for yourself.