It's been down for a day, and may be down for a few more. Looks like "Just build your own Internet" isn't a viable option for internet communists, everyone must learn of their peaceful ways by force.
Trying to get to Saidit redirects you to Saidit's Subreddit, in a sad state of affairs.
EDIT:It's come back up since then. Updates in the link.
That's a good point. I kept an eye on the voat refugees we got a while back. I never took saidit seriously as a platform, so I had no way to really identify their users. But I should have kept it in mind - I'm usually more mindful about that.
saidit is (was? undetermined until the root admin does something) the best of the reddit-likes.