Planetocopia. What would Earth be like if we tweaked a couple of variables? Surprisingly detailed analysis–possibly obsessively so.
Serafini’s Codex. Illustrations of an imaginary world imitating the style of the Voynich Manuscript.
On another note, I did not finish the 3-day novel. I got a lot of writing done anyway which is better than nothing at all. I also got distracted with studying Inform 7. I’ve been fiddling with code in an attempt to implement a puzzle that’s been stuck in my head for the last couple of days. Still fiddling–for a non-programmer at least, it’s quite non-trivial.