WiFi locator help

Hello,

So I had an idea after eating a kinder-egg today. The kinder egg has a little "egg" inside that has a little toy. And I wanted to make use of the "egg". I was going to make a Wifi Locator.

Essentially it would jsut be a little led that sticks out the top of it and it would light up when there was a wifi network avaliable. Possibly even an RGB LED that would change color according to how strong it was.

Does anybody know of any compact solution for this? If not wifi than does anybody know about one for AM and FM radio waves?

Thanks in advance

Wear one of these: http://www.thinkgeek.com/tshirts-apparel/interactive/991e/?cpg=clrss

8)

I was more so looking for something that I could fit in a small egg. So I could be like hmmm is there wifi here? Why tarnation there is!!!

Yes but you could cut out the detector from the shirt and use that.

Does anybody know of any compact solution for this?

You need to search ebay and google for ready made units.

The thing is i feel like i could just buy a usb dongle and use that, although those are for the usb which provides 5V, and I want this to be a 1.5V model so i can use a little disk battery. I'm not that experienced that I can modify something like that in that manner.