Is there a way to consolidate Direct Loans student loans at a lower rate than the standard 6.8%?

I have over $60k in student loans from graduate school. Most of them are subsidized and unsubsidized Direct Loans. Since I'm out of grace period in August I would like to consolidate to lower my monthly payment. However, 6.8% appears to be pretty high considering the lower interest rate environment. Is there a private consolidator (commercial bank) that would offer a lower rate? Even a 100 basis point savings would mean a savings of a few hundred in interest payments. Thanks!