One of the favorites in my collection. I picked it up "for parts" on Ebay a few years ago and it ended up just needing a little cleaning and a new battery. It is a bit beat up, but that just allows me to play it without worrying about scuffing up a collectable.
This is by the same guy that hosts the N-O-D-E website, and it it is a conglomerate of recent tech new/articles that I think hold some weight here. There is also a related YouTube channel that is worth checking out if this sort of thing interests you.
http://mosfet.net/