I like Etherpad but unless you give us a reason for posting this here that is HN-related, it should be flagged.
I think this is interesting for two reasons:
1. Open source web apps often struggle to maintain a "Try it" server. The interesting thing here is that Sandstorm (through our package ecosystem and demo server) makes that easy for any open source web app, and this is an example of that.
2. Since I wrote the code that powers that link, I thought it would be a great thing to "Show HN", per https://news.ycombinator.com/showhn.html "Show HN is a way to share something that you've made on Hacker News."
Sorry - I thought you were a new account. I'm using the chrome extension "Hacker News Enhancement Suite" and it highlights yours in a very-similar-color-to-newbie-color.