1) This is not something you can sign up for
2) This is not something you get paid for
3) All good things come in three, so that is why I added this one
As to the original question... There are some sites that still offer rewards for filling in (online) questionaires or receive spam. I only know one still, it is a Dutch site: www.euroclix.nl but I haven't checked those out in a long time (they did pay out though, I received cash several times myself)
One reminder to all tho...no referral links here...just the link to the main site without referrer codes please.