What's the rarest or most unusual computer-related item that you own?

A lot of interesting answers in this thread, here are a couple of my rarest ones. The machine I appreciate the most is the NORD-1 that I rescued last summer. I'm working on getting it up and running. Originally built in 1972. http://www.ndwiki.org/wiki/NORD-1_Serial_47 I've done some research and although only around 150 were produced it seems like at least 10 have survived and recides in museums or in collections at universities. Mine is the only one privately own I know of. Other rare systems I have in my collection includes : - DataPoint 2200 type A with serial dynamic memory, sadly incomplete and in bad condition. http://www.home.neab.net/gandalf/ClassicComputing/Pictures/DP-2200/Datapoin… - DataPoint 2200 type B with random access DRAM, complete but blew a fuse last time I tried to power it up. http://www.home.neab.net/gandalf/ClassicComputing/Pictures/DP-2200/Datapoin… Both systems have severe screen rot. I also have an Alpha/LSI 16 bit OEM computer with 32kx16 core memory and a custom terminal. It is part of an EDS instrument that came with an electron microscope. When I powered up the system ten years ago it showed the last measurement, but when I pressed the reset button it crashed and just showed a line of @ at the top of the screen. It's an interesting system and the architecture reminds me a lot of 68000 CPU:s, including the possibility to stretch bus accesses indefinitely and running DMA so it would probably be an easy task to build a modern board to make an interface to debug it. http://www.home.neab.net/gandalf/ClassicComputing/Pictures/Alpha-LSI/IMG_20… At the software level I probably have a nuclear power station simulator. One of my computers ran a full scale simulator at one of the Swedish nuclear power plants around 1990. I haven't checked the disk yet but there is a good possibility that the software is still on the 70 Mbyte SMD disk. G?ran