One of my upcoming projects includes a web developer tool similar to whois.sc.

Now, the obvious tools that need to be included are PR, Alexa, Compete, and backlinks. But beyond that I am looking for other tools for people to use.

What is it you would want in such a service (where you put in a domain, and it gave you information)? Reverse IP I think is a big one I will try to include. Any others? Domain age? What would you like?