how about an Enigma replica

[Thomas Radtke]

This kind of money buys you a ticket to one of the nicest cities in the world (and a visit of the museum of communication).

   

Edit - To say something more on-topic: I like the idea of further developing obsolete technology this way. What if the Enigma would still have been build in the 60th? You cannot see the electronics, so using an AVR instead of discrete transistors is ok imo. Not really a collectors item, but a piece of art. An expression of feelings I could probably share.