802.11 mini PCI cards: http://www.netgate.com/index.php?cPath=27_86
I've been quite happy with service from solwise for miniPCI adaptors and various wifi accessories.
I bought one of these and fitted a spare intel 2915abg minipci card: http://www.solwise.co.uk/wireless-pci-slot.htmI can only use it in ad-hoc mode so it's wep only, and then that interface is heavily filtered but allows openvpn access.
Paul