MoneyOnComputer

Anyone who likes to save money would love this site. It may not "earn" you money in the traditional sense (however it does have an affiliate program that starts out a $5 a referral) but anyone who loves shopping can use it to save money AND get cash back so I am sure you could possibly get people to sign up (only a sign up is required, not orders).
http://www.befrugal.com/cashback/?ref=TABTNSA

Looks interesting, i can't find anything on the FAQ - do you know if it's US only?