@sponge, yes, it has to be different cards. Sorry
@Everyone else: Certian cards (namely Atheros and some Netgear) can be re-mounted as wireless access points. But, you need to uninstall your current drivers, play email/phone tag with the customer service of your respecitve card, get the new drives and software, reinstall the card, and pray that it works and that you didn't break anything in the mean time.

The other method is to switch to linux, and go to this site. You are on your own from there out, as each computer has a different setup, and I cannot give out general instructions on how to set this up right for everyone.

Finaly, I have found that there are a few makes of USB wifi adapters that will run as an access point. I bought one 3 years ago at Fry's on black friday for $2.30 (after rebate, w00t w00t), and gave it to a friend. It works under Windows, so it is a cheap (but not free) solution that'll work. But just keep in mind that they have crappy range compaired to a real access point. There is only so much power you can get out of USB.

:::::Edit:::::
This is the exact model that I got. You guys are lucky she just called and told me what it is.

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