PeopleString is a community like Facebook where you can play games and make friends but the cool thing with PeopleString is that they pay 70% of all advertising revenue back to it's members. Your percentage of the revenues is determined by how many times a month you login. You can also make money by receiving postal mails or emails but it's optional.

Minimum payout: $25 will be paid monthly if you have enough money on your account.
Payment method: PayPal

Minimum payout: $2
Ads per day: 4-5
Per click: $0.01
Per referral click: $0.005
Payment method: PayPal/AlertPay
Price per referral: $0.26/month
Upgrade price: $80/year

Minimum payout: $2
Ads per day: 5-7
Per click: $0.005
Per referral click: $0.0025
Payment method: AlertPay
Price per referral: $0.35/month
Upgrade price: $90/year

If you have a twitter account with at least 50 followers then you are ready to make some extra cash from twitter. RevTwt post ads on your Twitter account and you'll earn money each time someone clicks on it!

Minimum payout: $20
Real posts between ads: 5
Per click: It differs from ad to ad
Per referral click: 20% of their earnings
Payment method: PayPal

Minimum payout: $9 for standard members, $2 for premium
Ads per day: 4-6
Per click: $0.01
Per referral click: $0.005
Payment method: PayPal/AlertPay
Price per referral: 10 referrals = $20, 100 referrals = $175.
Upgrade price: $12/month