We have terrible cell reception at our house: bottom of a hill, edge of a ravine. It’s just not happening. So I wasted some time yesterday (I forgot to enable Freedom–dumb) fossicking about for solutions.
It comes down to two basic choices, spend money on this:
Or have fun making one of these:
http://www.metacafe.com/fplayer/750707/how_to_make_a_cell_phone_antenna_under_5_minutes.swf
As you know, I have MacGyver tendencies. Sadly, I’m also the laziest person I know. Decisions, decisions. I guess we could always move. Or, hey, just do what we’ve been doing, which is shrug and smile and tell the world: we never answer the phone…
Nicola Griffith 
Looks pretty easy. I have a soldering iron!
Maybe I should make a bunch of those and sell them on ebay for $50…
Hmm, I could go all techno-geek and ask why he didn't mention that the length of wire that is the actual antenna is somewhat critical. The cans are just acting as reflectors and their size is not as important, but the actual length of the antenna can either significantly impede or enhance the signal strength. It's all about the wavelength. Sorry 'bout that.
Oh, Oh, make the thing! Make the thing!
That looks like such fun :D