You can consider foreign indicies like FDAX or MDAX (mini Dax) on the Eurex. Depending on your hours, you can also consider Osaka based Futures like Mini Nikkei 225 which is fairly liquid. Eurex is provided via Rithmic, CQG and CTS. Osaka Futures via CQG.
Meh. My bad. It was late; I wuz tired == cranky. But the way you put it, it sounded like "Trading $$Millions for 30 minutes a day!!" stuff. Having paid that price myself, I pulled what the shrinks call "projection." (Also, of course, this relentless-climbing market *really*does* have my nuts in a vice ("Whoa! Where's the emoji for *that* one!?!?").....)