Nice find!
The DWL-500 is actually a standard DWL-650 D-Link WiFi card and a PCI-PCMCIA adapter card included. The PCMCIA card is identical to the one you would get packaged alone, with the DWL-650 sticker, integrated antenna, everything.
The PCI adapter has a Ricoh RL5c475 chip and works with many other PCMCIA cards.
The DWL-500 is being replaced by the DWL-520 which has the WiFi electronics integrated into the PCI card, and an external antenna connection (reverse SMA?)
At $40, it's worth buying just for the DWL-650. Toss out the PCI adapter. That's what I did, anyway.
The DWL-500 goes for less than the -650 on eBay.. go figure.
