QUOTE (Phillip Brooks @ Mar 30 2009, 11:34 AM)  
 
Hi, I hope you don't mind me jumping in.  We do release an API for the Wi-Spy 2.4x, it currently isn't published, but we'll send the documentation to anyone who emails us.  If you are a developer and own a Wi-Spy, send us an email!  There is an open source version called SpecTools, and that was created by the author of Kismet.   
We have a perl script that will convert the live data into a CSV, which a lot of people find useful too. 
The Wi-Spy will show all radio activity in the 2.4GHz band like Wi-Fi, microwaves, cordless phones, bluetooth, and many others.   
Thanks for the link, Phillip.