*mturk : This one takes the most learning to actually get good at. But if you put in the effort and learn it, the rewards will be the best by far. Check out mturkgrind for some great help and tips.
*Gifthulk : This one is borderline worth it to use. My approach is do the bare minimum and it's very low effort for very low reward. But since it's easy, I figure might as well.
*Bing Rewards: Note that this is worth it currently. They did however just announce that in the coming weeks it's changing to Microsoft Rewards. It seems like it will be very similar. One perk to note is that when it changes, existing Bing rewards members get upgraded automatically in Microsoft Rewards. So it's still worth signing up for.
*RewardShopping : This is formerly SuperPoints. Nothing really changed except for the name.
*DraftKings : I prefer DraftKings over FanDual because they have quarter games. FD starts at $1 minimum bet. DK also has more sports to play in.
*ibotta : Enter code "ptbaq" without the quotes at sign up to get a little bonus!