Some cube/mac questions :)

[mcph at olemiss.edu]

Hello,
   Santa was very good to me bringing me a 450 Cube for
christmas.  I'm planning to do some upgrades to it over the
next few weeks.  My understanding is that the best video
card that will fit in the cube without modifications is the
mac edition Geforce 3 card.  Does that hold true for both
the OEM and retail versions of the card?  Is ebay probably
the best place to find them?

My current internet setup is with an alcatel usb DSL modem
(it was free).  I also have a winXP based laptop.  I'd like
to be able to share the Dsl connection wirelessly.  Does
that require a base station or can I just get an airport
card (and the PC equivalent) and do some sort of peer to
peer setup (effectively making the cube the base station)?
If that's possible how difficult is that to set up?

Thanks alot :)
Michael