As far as I know, if you want to raise money to get your idea off the ground (i.e., build the MVP and test the premises), you need to either invest your own money or ask friends and family members for it.

Do you think it would be useful if we had a platform to connect entrepreneurs looking for this get-my-idea-off-the-ground money with people willing to invest in such an early stage?

I believe it could be worth it for both sides, since the amount of money we are talking about here is usually small.

For instance, most software-related projects could probably be launched on a $10k or $20k budget, and I believe many entrepreneurs would be willing and happy to give up 10% or 20% of the project in exchange for this early investment, especially at a point where all they have is an idea and a business plan.

For the investor it could be worth it because, despite the risk being higher, the equity he would get would be pretty high for such a low investment.

I don't believe there are similar concepts around. Kickstarter is not equity funding, for instance, and the other platforms require you to already have a product and some traction to show before you raise money.

Could this fly?