From the Select Committee on Benghazi Minority Site:
Instead of taking concrete steps to enhance the safety and security of our diplomatic corps overseas, the Select Committee on Benghazi continues to squander millions of dollars and has nothing to show for it other than a partisan attack against Secretary Clinton and her campaign for president.

$4,816,375 and counting as of 8:50 a.m. 9/23/15 – SPENT BY THE SELECT COMMITTEE ON BENGHAZI TO DATE*
(*Based on actual expenditures publicly reported here and then forecasted using the most recent month’s average daily expenditures.)
This calculation does not include the costs of: the independent Accountability Review Board; the eight previous reports by seven Congressional committees; the time, money, and resources consumed by federal agencies to comply with Select Committee requests; or the opportunity cost of not spending this money elsewhere, like improving security for our diplomatic officers abroad.
The Select Committee on Benghazi has been investigating for 533 Days, which is longer than the investigations of Pearl Harbor, the Kennedy assassination, Iran-Contra and Hurricane Katrina.

The Benghazi Research Center estimates that costs to the taxpayer could exceed $20 million when all is completed.
Think also of all the expenses incurred by the media in covering this nothingburger — time and money that should have been used to illuminate real issues and policies for the benefit of Americans.