For neobux you will start by only earning around a few cents per day. But after a while you will start earing money by either earning referrals or by buying them which will cost you money from either your account or paypal. You can also use this on social networks such as facebook or myspace. i have earned over $250 by this website. it has taken me a while but now i am making around $75 a month.
For prizerebel you earn credits, this doesn't earn you money. Instead it earns you credits for prizes. the prizes are memberships for many websites like club penguin. Also like video games, consoles for video games, and also gold cards for x-box 360 and more! The best thing is that you can is you can post your referral link on facebook or myspace. Your referrals also earn you around 20% points.
Beware these are the only ones that ive tried that work. The ones i tried that don't work are (treasure trooper, cashcrate, and ad.fly) happy moneymaking