My first cantenna:
http://tarafoundation.org/cantenna.htm

I basically followed the design plans at, except substituted a V8
can:
http://www.turnpoint.net/wireless/cantennahowto.html

I haven't done precise signal strength measurements, but I'm getting 3
and 4 bars, when I used to get 1 and 2 and occasionally 3 with an omni-
directional antenna.