The adapters in question are Sagem-branded Z-Com XG-703A adapters. They are sealed in anti-static bags and presumed to be new.

These adapters have an Intersil Cohiba chipset (ISL3887 + ISL3686). Linux support is well established with p54 (which will support Station, Ad-hoc, AP, Mesh, and Monitor [with injection] modes). The devices will also work with 32/64-bit Windows XP, Vista, and 7. Windows drivers are available here.

The price, again, is 2 BTC shipped worldwide. This is stupid cheap.