That’s what I get for setting setting up some posts in advance and taking some time off!

$50 for emails with Sanborn?

BERLINCLOCK

I’ll go dig around in the comments everyone has left but am not sure how this will help us any more than Berlin did.  My first thought is that it will be easy to get lost in trying to assign meaning to the words Berlin and Clock instead of trying to reverse the ciphering.

Added: Audio interview thanks to Franky (http://goo.gl/eQKDLC)

And the Clock in question:

Mengenlehreuhr

It would figure that someone like Sanborn would like Mengenlehreuhr…

Again, keep in mind that we were only to find the phrase “berlin clock” after decryption: attempting to use this particular clock to decipher K4 is not going to help.

The context with the other 97 letters will be certainly interesting in the end though.

-Kryptosfan

p.s.  I do think that this clock is supposed to help us understand a final message or experience (i.e. K5), I just don’t think it was meant to help solve K4.  If Kryptos is the progenitor of his artwork immediately following then we can see there is some relationship with the copperplate and illumination/shadows created by it with a light source.  The simplest method would be to look through the cutout letters but shining a light through seems more likely to me personally.