Drop dead gorgeous is in the eye of the beholder, of course, but If I wanted to stay with wood, I think I'd want to find the best Amboyna or Olive blanks I could get. I've seen some pretty gorgeous Black Ash Burl, York Gum, Vasticola, and Yorrel burls, too (or most any of the Aussie burls).
On the non-wood side, I'd lean toward TruStone (I like the Turquoise), River Buffalo Horn, or Pine Cone.
Then, if you want to consider castings, look to Cactus Skeleton, Snakeskin, or any of a wide variety of worthless wood and segmented treasures offered here.
The journey is the reward, so enjoy the search!
-Barry