Here are some that I heard about and recently found.
Several chinese woods, which you can get from rarest woods, tzu-tan, huang-huali, Jichimu, Hongmu.
American smoke tree burl(chitam?)
sandalwood burl
curly pernambuco
Black and white ebony burl
African blackwood burl
There are a number of woods such as brazilian rosewood, pernambuco, madagascar rosewood and a number of others that are rare, and no longer allowed to be exported, can still find old stuff.
Old growth curly koa
Hawaiian kawili
Quality ironwood is becoming more scarce. In the U.S. you must have a permit to cut it and only dead trees can be harvested.
Blue mahoe
This is a short list, I am sure others can give you a much longer list.