From: coderman <coderman@gmail.com>
Sbject: Re: [tor-talk] Using SDR
On 2/5/16, Sean Lynch <seanl@literati.org> wrote:
> The older, lower-tech version of this trick is to use a high-gain antenna
> like the Cantenna or a Yagi to use a public wifi AP from a stealthy,

Initially, I was confused about this.  To me, a "Cantenna" was Heathkit's name (in about 1970 or so) for a dummy-load built from a
1 gallon paint can with a non-inductive resistor inside, immersed in transformer oil, capable of dissipating 1 Kw or so.  
Showing my age.
Now, on Google-search, I see it as an antenna built with a tin can.
        Jim Bell