yesterday I received a new WiFi Card as I am constantly searching for something better.
I got the Socket WLan CF Card an I am really pleased with it. I installed the drivers on every available iPaq, the SIMPad on PPC2002, WM2003 and NET4.1 and everything ist working great. It has been a long time since I could say that about any hardware I bought.
And the best is, it's really low power. They say it take only 20mA in reveiving mode which is quit low.
So just to let you know if you are searching for a CF-Card for your device, take a look at the Socket card.