Topre Realforce 87U. (I also have two HHKBs, which are similar to the Realforce. I have not decided which I like better yet; same keyswitches, but different in many other ways.)
I also have a "Siig MiniKey" or something acquired new in box from a cheap/used electronics reseller, with Alps switches.. for $5.
Actually my friend bought it on a whim. They had a huge crate of them there, all new in their boxes, recovered from a sell-off from some corporate warehouse or something. I got it from him later, when I saw it, and I could instantly tell it had Alps switches in it. He said it was only $5 so we ran back to the place immediately -- but someone had already scooped up the entire crate of them. The place selling them had no clue they were worth a bunch of money. Otherwise, I would have bought all of them myself. I guess someone else had the same idea as me.
Oh, and this is true of both the Realforce and the HHKB Professional; same switches, different layout.
Of all the things in an ordinary office or home (including toilet seats and such) phone handsets and computer keyboards tend to have the most germs. One anti-germ measure I use is to replace my keyboard every year or so, but replacing the Topre every year is more than I want to spend. Replacing just the keycaps would control germs just as well as replacing the board, but where would I buy keycaps for a Topre?