All sites promising high returns are, across-the-board, scams. There is only one that I know of which wasn't run as a scam, but they lost all their investor's money through carelessness anyway and are slowly trying to pay back the initial investment.
Any system that solicits small investments across the internet is almost certainly incapable of returning a profit to those investors.

I do have first-hand knowledge on this subject because I run an investment program using only my personal wealth and i do what HYIPs claim to do. I am not soliciting investment online, though that is a possibility in the distant future. I would expect that anyone who invests in my program (if I accept outside investment) will meet me in person, have all my contact information (phone, email, name, address; all of it), and would have a signed contract for the investment agreement.

A person running a legitimate program will not spend their time looking for investors. They will spend their time looking for insurance companies and financial auditors - which is exactly what I am trying to do. They care about securing funds, rather than acquiring them.