Patrick Lafarguette, author of the 3Com 920 and 940 drivers as well as the Intersil Prism wireless driver has today published yet another wireless driver on BeBits. This provides the first 802.11g support for BeOS, for Intel PRO/Wireless 2200BG chipsets.
The driver is in two parts, one is the BeOS driver and the other is the firmware, that must be downloaded by the driver at runtime.
The driver can be found
Here. It currently only supports infrastructure mode operation (BSS) and has no WEP or WPA support, but its more than enough to get you onto your network.