Lots of fun inspiration!
Moss balls - could work with a bit of experimentation
Ciclid rocks - also could be a nice basis for some interesting rock dwellings!
Cappadocia - Wow. I could certainly see the casanii living in those! I've taken inspiration from lots of interesting dwellings around the world, but those are particularly cool
Dinotopia - I had fun introducing my daughter to these books a few months ago. Another one of those things that got mixed into the general melting pot of my subconscious when fleshing out Twilight! So many amazing buildings I would love to try and construct for the fubarnii...
Houses - More fun concepts
Are you going to make some scenery?