The CBOE announced they will start listing Binary options on the XSP (mini SPX) starting June 15th.
They offered binary options on the SPX some time ago, but discontinued it due to lack of interest. Looks like they will give it another try.
Link to details,
[Update - Cboe Options to List Mini S&P 500 Index Binary Options](https://www.cboe.com/notices/content/?id=59880)