Rust art, bootcamp, and the best place to plan your base.
The site is pretty popular, with 1000 people using it per-day. That has driven up costs. The team are hoping to grow the idea, with an iOS version, but obviously that costs money.
Speaking of iOS, there's a new iThing server admin app available. RustySpoon iOS administration tool will allow you to see who's on your servers, and you can kick and ban with a stab of a thumb.