We ran across this site pufip.com Its one of those things where you have no idea how you got there but once you do its kinda interesting.
The site uses a number of scripts that grab data from search engines and site rank sites and gives you a Price that your website should sell for.
Viewing the data for a few sites that I know the statistics about I can say the price they return really isn’t accurate but I guess you could say its relative.
In other words if you compare a couple sites then if that site sold for so much your site would sell for the price listed.
Anyway if you got some time to kill visit