Computer History Museum in Mountain View is probably one of the better ones. Along with its own collection, it has a fair number of artifacts from the closed Computer History Museum in Boston. It's mostly focused on pre-PC era.

In Germany I know of:

Heinz Nixdorf Museum in Paderborn:

http://www.hnf.de/en/museum/video-about-the-museum.html

Computer Games Museum, Berlin:

https://www.computerspielemuseum.de/1210_Home.htm

Museum for Communication, Berlin:

http://en.mfk-berlin.de

The National Museum of Computing in Bletchley is good!

>> are there good computers museums where you can see these machines?

How about a good place to donate one? I've still got my Interact (1978) and its original box. I think I've also got a fair number of issues of "Interaction" which was a Detroit area users newsletter produced by (I think) Steve Cook. Mine also has the extra 2K rom monitor program by Walt Henderson. It really is collecting dust but it powered up last time I tried many years ago. I'd make the effort to gather all this up if I thought it would be going to a good home.

There's a nice one in Cambridge, UK. Most of the machines are on and ready for use.