Before i begin to tell you about the kind of a website i find missing in www,let me give you some insights.I have a finance site and got about 30 visitors per day some months ago [the site has now been sandboxed].Every visitor was through a long tail keyword.You just would not believe the amount of long tail keywords you can generate .And keep in mind that those long tails are not present in any tool.Keyword tracker,google adwords - everything did not show the long tail i was getting. I was simply stunned by the long tail traffic through the finance niche.You can get at least 500 long tail finance traffic everyday if the site has been out of the sandbox.But the important thing is finding the long tails. So i am asking your opinion on this sort of a website model: Suppose say there is a web site that buys the list of keywords and sells it to others - that would make our job easy,right?I mean if you are ranking no.1 for a niche,you can go to the site and sell the keyword list.The web site owner can then sell the list to others and make money.It can be a membership site too.For each niche keyword list access,the member can be charged.You will not only get the long tail ideas but will also get the exact amount of searches made per month. So many people start a web site around a main keyword which adwords tools says gets around 30000 visits each month.But when the webmaster spends around 10k dollars and gets the site to the top serp,he finds that it gets just around 30 or 40 visits.This happens,right? What do you say about this web site plan? Remember guys - long tail traffic is amazing and the fact is that no tool is giving these keywords to us.I am telling this from my own experience. TIP: TIP1 ::If you want to know some exact searches for the keywords,make sure to check out flippa.Some times,the web site owner shows the analytics accounts screen shots with the keywords too.So you can get a list showing at least the exact searches for a keyword and also the main keywords,if not the long tails.The adwords tool showing the exact searches for the keyword sucks sometimes.Some times,the tool shows 27000 searches per month and when you get the top serp,you end up with just getting 5 visitors !! horrible. TIP 2 ::Use yahoo answers Real google searchers come here and search for answers.So you can get a lot of long tail ideas from there.Just go to the desired niche and see what they want.I did this for my finance site.hope that helps.