You've got one of these: MakeThumbImage.aspx

When all else fails go back to what I should have done in the first place.  I duplicated the page, and created an empty page also.  Moving from the duplicate page to the empty page resulted in a log out.  So, I started removing module 1 by 1 from the duplicate home page and bouncing to the empty page until the problem stopped.

It was the Flash module in the center of the page that was causing the problem.  Not sure how to debug that, but I will send a note to the module author.

I've created a role that allows you to see the 'Empty' page under the Home menu, if you care to take a look.  You can go anywhere on the site and remain logged in.  As soon as you go to the Empty page and then move to another page, you will get logged out.  The only module on the page is the flash module.

Thanks for your help!  Thanks big time for introducing me to Fiddler, I've have discovered a whole new world of things to address.

Rob

If you like Fiddler, you should also check out FireBug for FireFox, and get the YSlow plugin.