McAfee is offering a free Wi-Fi scan to determine whether your network is at risk: The McAfee scan (which I learned was built by the folks at Wireless Security Corporation) uses an ActiveX control to check on your Wi-Fi network from a client machine. It's free, and it offers sensible advice about WEP, WPA-PSK (WPA Personal), file sharing, other users, and client access speed in my test of two Wi-FI networks I run in my office. It's a great free tool. David Haskin writes more about the Evil Twin detection that it also offers. I apparently have no such animals in my vicinity.