I was checking out my Twitter Followers and this led me to a website called MicroDesign.
At the bottom I saw this:
I clicked through to the Fluidbook site.
And I did the demo.
It's very interesting. Performance was OK -- not great, but not terrible -- even on this crap PC (which means it should be great on your PC). The user interface was clean and it was the first time I've seen online publishing done in a sensible and actually readable way.
Go have a look.