I have a "The Original Macintosh' 128k (this is a macintosh BEFORE they were labeled 128k.) .(you can find the story here: http://www.geocities.com/coiuspcrepair/omac.html)
This has not been altered at all (like with the 4MB extension hack), and it boots to the desktop with no errors. I borrowed disks from a friend (before he lost them) 
to test it.
It is a little yellowed (as can be expected, but it is still more biege than yellow) and the battery is dead (good luck on me finding one)
I have seen these units go on ebay by themselves for $60, and they are in worse shape than this is. Also, most of them have the '128k" suffix added to them.
anyway, i am thinking about selling this. How much would this be worth?
if anyone wants to give me a good deal on it, ill sell it without thinking.
you can email me at pledoux@gmail.com
Seeing as no one wanted to made a trade/offer, it is now on ebay.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5803941203&rd=1&sspagename=STRK%3AMESE%3AIT&rd=1
Go for it while you can
I upgraded the ship-to locations as I have gotten 3 messages asking If I would ship to Japan. I now have shipping for EVERY location
*EDIT* I don't think the last link worked right (it doesn't for me), this is the link