1NY.com - Elon Musk bought back X.com which he left in 2002
" X.com is one of the few single letter .com domain names, and I would argue that it is one of the most valuable domain names. The X.com domain name was originally a financial services company co-founded by entrepreneur Elon Musk. X.com was the predecessor of PayPal, and it does not look like the domain name has been used independently from PayPal (or Ebay) since then." - Elliot Silver - Read Full Article
Z.com sold for nearly $6.8 million in 2014
X.com is the best and the most valuable domain name so far. Our prediction will be around $10M to $800M max.
Source: Domain Investing
1NY.com is for sale