MegaMacs offers the OEM Mac OS X 10.6 Snow Leopard Server, model no. MC190Z/A, for $279.49 plus $9.96 for shipping. That's $5 under our November mention and the lowest total price we could find for this software by $98. This OEM version doesn't include a box or manual. It supports an unlimited number of clients.

Note that MegaMacs mentions an expiration of January 18 at 1 pm ET; the price is still currently valid.