Slava Pestov has moved the main Factor website to a new machine and is running it on the Factor web server. It's also running the Factor code browser. I've retired the browser I was previously running on factor.modalwebserver.co.nz as a result.
Slava is using Linode to host the site. Linode provides 'User Mode Linux' machines within which you can install Linux and use it for whatever purpose you want. This is what I also use for my websites and what I previously hosted the online Factor browser on. I can highly recommend them. Great service and it gives you much more freedom to do what you want - assuming you don't mind setting everything up yourself of course!