I get asked this over and over again by different readers. The question always goes something like this: I have a great idea that I know is worth lots of money. But I have no money and need lots so I can bring my idea to realization/patent/market. How do I present my ideas to investors with 100% assurance that they won't rip me off?
Do you want the short answer? It's that you can't get that kind of assurance in the business world. All you can do is minimize your risks. Did you check out the business reputation of your potential investors? Have you considered getting a provisional patent? Are your investors willing to sign a confidentiality agreement? And just why can't you get your idea to the working model level before approaching investors?
I have a great article written by a friend of mine that I think those of you with the above question should read, it's called Patents Are Not Puppies and while it is written about trying to sell a patented invention, it does apply to those of you without patents as well. The point of the article is that most inventions do not make money, while most inventors act as if their inventions are worth lots of money. However, nothing ventured, nothing gained, the following article is also very useful Sources of Angel Investor Funding.