Ok, firstly, this site is definitely a ponzi/HYIP.
Do not give them any money.Until they stop paying, though, you have nothing to lose (and a lot to gain) from signing up and just leaving the website open.
How it works is you sign up and visit a webpage. Every 15 seconds, it reloads and you get money. The maximum you earn per day is $3.5 and the minimum withdrawal is $100.
Here's the non-ref link:
http://www.automoneysurf.com Remember: don't deposit anything. Just take what you can and scram.
mod note: ref link removed