I have a shirt with this design, but I absolutely love this Fibonacci Sequence necklace from Boutique Academia (wow, do I want this!).
The shop has some fabulous offerings for us geeky folks! My three other favorites from the site are the Neurons:
The Pleiades:
Tree Ring:
Great Stuff!
SheWalksSoftly 
2 responses to “Boutique Academia”
These are gorgeous! I think my favourite is the tree ring, I could stare at those imperfect circles forever!
Nature has far better patterns than humans design.