yeah it's my partner's dream, been wanting it forever. Apparently the guy still blogs about it and is working on a 2.0 design. http://quidnon.blogspot.com/
Honestly, you can get an existing 35 foot boat for way cheaper than the $50k those kits are supposed to start at. That design also looks like while it might be a lot of space, it'd be garbage for actually sailing it anywhere. There's no point in slapping some sails on a box just to call it a sailboat.
If you're not strictly looking for something that moves under its own power, hell, I've seen plenty of 30'+ powerboats going for free. There are lots of old used boats around in certain waterfront areas, and they're generally super cheap.