Privacy oriented, open source, user funded, focused on quality content, aiming to develop a user-centric moderation system like slashdot and stack exchange that puts moderation into the hands of the people who participate in each individual community.
If you have a reddit account, you can visit /r/tildes and leave a reply in the sticky invite thread to get an invite code within a day. Or, you can send an email to [email protected] to get one.
It's worth noting that Tildes is created and operated by Deimos, the same guy who created reddit's automoderator and subredditsimulator.