What's the furthest you've been able to receive Wi-Fi from?
...either connecting to it or just scanning for spots?
The furthest I've been able to do was about 7.6 miles, using a Lenovo G530 laptop barebones. I had line-of-sight to the access point and was elevated on a hill roughly 600 feet above it. I did not connect to it, but the signal strength was sufficient to.
I've tried to connect to the public access hotspot (or series of them) Duluth has installed in the Canal Park tourist district from a site on a hill about a mile away from it, again from my laptop barefoot, but was not able to.
As for my own access point (Linksys WRT54G), I've been able to connect to it, ping it, and access the internet from about 750 feet from my home (barefoot), although it requires me to hold the laptop in the air. I do not have a WiFi-enabled phone. There's a place on the road about 3,700 feet from the access point with line-of-sight to my house that I believe I could connect to it with an external antenna.