Yes, I have heard that the Sinclair is sort of a collectors item these days, but mine isn´t for sale...I am absolutely a hoarder, I love to go to "flea-markets" and look for odd things. My apartment is full of stuff, mainly old cameras and radios...But a lots of other strange stuff too...
The "OM" thing is rather odd, sofar I haven´t met anybody who knows how it works, it came with a instruction that don´t make sense to anybody, (not even a civil engineer I showed it to !) Guess those mechanical things are from the 1940-ies and 50-ties. I remember the Sinclair as a extremly boring thing - You couldn´t do that much with it besides programming basic..
Well, time to hit the bed, I can show more of my collections some other time ! 
raimo