I discovered recently that a "Free the Net" wifi node had appeared within range of my building in SF. This was fortunate as the access point that I had previously been leeching from now was no longer unsecured. (Took them long enough...) The "Free the Net" network is a basically the closest thing to free community wifi in SF. There's info about it here:

http://sf.meraki.com

It took a bit of fiddling with my cantenna, but I finally found the right direction (straight out the window) and polarization (horizontal) to get a reasonably stable connection to the access point. It was still a little marginal though, so started looking into various options to improve the situation, hopefully in a way that would not require me to mount an antenna on the roof of the building. (I can get the roof, but I'm on the second floor of a four story building, and at 2.4Ghz, a cable run that long would probably introduce unacceptable signal attenuation.) My first thought was a higher gain antenna, though most of good ones seemed to be quite large and unwieldy. But then someone showed me this:

http://www.metrix.net/valemount-networks-kxs30sg-p-438.html

An 802.11b/g wifi card with 1 watt of TX power. I didn't think they made such things, or that you can buy one in the US, but apparently they do and you can. I ordered one and it arrived today. According to the client survey tool on the remote node, my signal strength more than doubled. (I had been using an Intel 2200BG card previously.) Unscientific web tests show I'm getting about 1.2Mbps download speed, which ain't bad for free.

Oh, and it's based on the Atheros 5414 chipset. It works with FreeBSD out of the box, and since it's Atheros there are all sorts of funky things you can do with it.

I am suitably impressed.