I came across these sites the other night when looking for drivers for one of my Siemens Speedstream 1024 cards.
http://linux-bcom4301.sourceforge.net/
http://ndiswrapper.sourceforge.net/
For those having problems with the card, note that there are two versions of the card. One uses a Prism2 chipset and works for me with the orinoco_pci module.
However, the other uses a Broadcom chipset. No module for this chipset exists (yet).
The first of those websites is a project to write a module for the chipset. It may take awhile, as Broadcom is supposedly not responding to any emails concerning that chipset and Linux support. The specs on the chipset are blackboxed too, I read, so it will take some smart reverse engineering to get it working.
The second website is a project that aims to allow Windows drivers to be loaded as modules. Its similar to
Linuxant but its open source and free.
Just thought someone may find this useful...