Today I saw a domain with 15k rank and it has nothing on it, no content no traffic etc..
can anybody share the secret?
Why don't you let us have the domain name in order to take a look at the web analytics, and looking at the source code etc.
I'm guessing you already look at the whois and or Wayback to see if the domain is older or once had stuff on it. If its a new domain and ranking like that then this would be something too look into..