Here’s a three part video series from Paul Offord demonstrating SQL Server performance analysis with Wireshark:
http://www.youtube.com/watch?v=fY9S72FJbmE
http://www.youtube.com/watch?v=lM0p8ng_Yo4
http://www.youtube.com/watch?v=vVxyFl65Yx0
Paul loads the Wireshark CSV output into Excel and uses formulas to calculate the difference between network request and response times. The CSV output could just as easily be loaded into a SQL Server table and the same values calculated using subqueries or analytic functions. Paul charts the results in Part 3 of the video. There’s a good illustration of blocking in one of the charts.
SQLscope 