some quesions about HYIFund.

Yes, absoluty right. supposing you invest $10, you will have a total investment of $12.5 thanks to the "gift" they give you. On average you will get $0.13 of interest each day. If you don't compound the interest, you will need around 100 days to get back the money you invested. So the only way to make this investment really profitable should be wait around 200 days, in while you compound the interest, before start to withdraw the interests. At that point you should have an investment of around $100 that give you an interest of $1 daily. The question is, will they be still active after 200 days? ;)

ah.. so this means I should hold my investment for 200 days and then afterward I will stop the compounding so the interest will go to my available cash balance.. But do you think the program will stay live till those days?

The 200 days is a "target" I've said to let the investment be really profitable. If you invest $10 and compound the interests, after almost 200 days you will get $1 per day. But, obviously, you can decide to don't compound the interests, and get back $0.13 per day starting from the day after your investment. In this way, you will need almost 100 days to get back your money. Then you will earn $0.13 per day ;) Who can knows if this program will stay live after 200, 100 or 30 days? I guess you know what happened to geniusfunds. If you asked to some investor the past month, do you guess they will stay live in the next 6 months, I bet all of them would answer "for sure!". Keep in mind HYIP are a big risk. The possibility you lose your money is really high. So my suggestion is: If $10 are a lot of money for you, and you can't afford to lose them, then keep you money. There are lot of ways to earn money on the net without risking your own money. If you can afford to lose these money, and accept the risk, then compound the interest for a while. If the program will not disappeared you will get back much more and faster.

can you recommend a trusted site to invest our money in it ?

3oooof, there are legal companies, which are real traders and even they have guarantee that you can't lose your money as investor, because they have emergency fund, which provides protection from any losses. Such sites are http://primarypool.com/, alpha-money.com and others.

I can withdraw the principal? or you mean I can get back my money through the interests earned?

This is absoluty false! Your principal is the investment you done, and as they clearly explain in the "our plans" section: "Once funds are placed into the "Investment Balance", they cannot be removed, and the investment never expires.". This means you can withdraw the interests if you don't compound it, but you NEVER will be able to withdraw the principal, or the interests you compounded. I guess, maverick, when you're talking about the money, you should give precise, trustable and truth indications. If you don't knows their rules could be better stay quiet instead of giving false informations that could push someone to make a mistake!