Kusudama is your keyword if you want to learn how to do these :)
The 5 intersecting tetrahedra is particularly cool, and I've used these instructions to assemble it <a href="http://origametry.net/fit.html" rel="nofollow">http://origametry.net/fit.html
ciroduran · · focus · HN ↗
The 5 intersecting tetrahedra is particularly cool, and I've used these instructions to assemble it <a href="http://origametry.net/fit.html" rel="nofollow">http://origametry.net/fit.html