incrediBILL - 7:07 am on Apr 2, 2008 (gmt 0)

I've been watching them for quite some time and this statement from their site is a real winner:

Our crawler does not have a "name", yet. Instead it announces itself to be a standard web browser, a "Mozilla 4.0" kind-of-browser compatible with the browser Microsoft Internet Explorer 6.0, running on the Windows NT 5.1 operating system.

They could actually include their path in the MSIE user agent, others do that, nothing new there.

Sorry, if you can't identify yourself properly you can't play in my sandbox.

End of story.