FGI Research - They do not send many invites out, maybe a few a month and you will not qualify for them all. However, you can earn a little extra spending change with them. The average pay per survey is $1-$3 and others surveys offer a specific prize or sweepstakes entry. The incentive for each survey will be clearly stated in each survey invitation you receive. They also offer referral pay and you receive your payments through Paypal mostly, but it may also be received through US Mail. Payment is processed once per month, for all studies that were completed in the previous month. You can check them out here: https://ld.fgiresearch.com/supp/asurvey?uid=46743165&cd=DA34FD86D7&src=3&rfid=38748
Iposis i-say - Here you can earn points for surveys taken, which you can redeem for gift cards or use for prize drawing entrees. They actually have some really cool prizes too.
Check them out here: http://www.i-say.com/
EDU Research Group - They offer a $5.00 registration bonus! You receive survey invites sent to your email address pretty often, depending on your specified interests. Your payment is received through Paypal or Amazon.com gift cards. The minimum cash out amount is $25.00. Here is their link: http://www.ergsurvey.com/