I have developed a new tool which shows the PR that each of your links is passing to your site. Using the Google PR formula the tool checks the PR of each page that links to you and then analyzes the number of outgoing links on that page to calculate the PR that each link is passing. Check out the backlink analysis tool and please let me have your feedback and results. If you run the full script (requires an API key) you can download an Excel spreadsheet of the results to analyze further. The tool is totally free as well