Here's what I think would a valuable tool. A keyword density analyzer that will take a url as input and spit out the most relevant keywords on that page. This way, I could go to a sponsors site, run the utility and find out what they are optimizing for. Then I can target those same keywords on my site. I don't know if something like this exists, it does, let me know, if not, it would be a great tool in the DP toolbox. MN
Check out this tool http://www.gorank.com/analyze.php It's a Keyword Density Analyzer and isn't the prettiest tool, but it does what you want. Also try searching Google for Keyword Density Analyzer and you get some good results.
But what I'm talking about is a tool that does not require the input of a key word, but one that will just read the page and display the word density. From there you can extrapolate the key phrases.
You don't actually need to input a keyword with the tool. Just enter the URL, submit and it will display repeated words and phrases with their density/prominence etc. You might also try: http://www.ranks.nl/tools/spider.html A similar tools with lots of formatting options.