U.S. futures are sharply lower after the Greek vote, and CNBC will have live coverage of the aftermath tonight at 8 p.m. ET.
The Greek people voted resoundingly on Sunday to reject proposals from their European creditors.
S&P 500 futures fell 1.5 percent in early trading after 6 p.m. ET (2200 GMT).
Once the magnitude of the Greek vote became clear, the euro began falling against other major currencies, and European stock futures sank (led by a 4 percent decline for the benchmark German DAX).