Yes, the pringles can looks like it would work...I like the idea

. I know you want to use something that you already have...and you can probably get it working. Good luck with the drivers.
However, you can spend just a little money and get an updated card that you know works. I looked them up at a large distributor and there are a few options you might consider. 3-com and some other large guys make cards with external antennas, you just have to find somebody that can sell you one.
There are cards with better built-in antennas - one is the Hawking high-gain card, it has a 6 dbi swivel antenna, which is directional and it´s $99 retail, which means you can probably buy one for a little over $50 somewhere.
The zyxel 91-005-016009 card with external antenna only retails for $69. It has an RP-SMA external antenna port.
So they
are available and pretty inexpensive and would give you the latest g technology, which would allow b links as well.
Good luck, this is a great application for wireless...