I want to develop a prototype to demonstrate to investors my idea in a practical way, hopefully securing funding to develop a full working product.
My concern (however unfounded) is how I can stop potential investors from taking my idea and running with it, without me.
I can't patent my idea as it is a particular implementation of an existing and open technology, however it differs in many ways and brings a lot of unqiue features with it, and it will be a lot of work to even implement the prototype.
No investors are going to sign an NDA and that tends to be non negotiable with them holding all the cards.
So, what protections can I take to protect my work and idea?