Yep, like everyone else is saying, surveys and offers. I'm dq'd from like 80% of surveys too, but just be patient and persistent. However, even on days I don't do a single survey or offer, I still make about 250-300sb, sometimes 400+sb from the passive/semi-passive tasks pretty easily, w/o too much effort/thought.

SBTVtoolbar (NOT the extension, as it's not passive) - 60sb

Mobile apps. I use separate phones for all of them. - 50-100sb

Watch (It slows my computer down like crazy so I do it on my tablet somewhat passively throughout the day) - I usually average around 60sb

Sponsored Videos (Binocular Girl, Laptop Guy, etc.) - I always run the All You Can Eat SB when I see it, and have 2 of the others running at one time, if available. - anywhere from 20-100sb a day, depends on availability.

nCrave. Always have one running in background when they're available. Same with sponsored offers - 20-100sb

To-do. Takes 10 min to cross them all off, except the complete a survey lol. - 7-?sb

Inbox. You'll usually see a few Watch for 1SB, or super quick, easy 1-click offers.

There's loads of other options, but this is the routine that works best for me, and keeps me hitting the daily cap on lazy days, or when I just can't be bothered/focusing on other sites.